Who Are The Living Ghosts?

A living ghost is a 'disgusting' but perhaps accurate term applied to a person who has come to the UK to claim asylum and been unsuccessful http://www.church-poverty.org.uk/campaigns/li..

Once this happens, and if his/her appeal fails then there is an expectation that the individual will return voluntarily to his/her country of origin, and if this does not happen he or she will lose all access to public support i.e. no rights to accommodation, no rights to seek employment, no rights to claim government benefits, no rights to social care and the most basic rights to medical care.

In this situation, a person becomes virtually invisible hence the term 'Living Ghost'. Nobody really sees the living ghost except when crime is committed or when the housing shortage hits an all time high. This is the time when the living ghost is most noticed.

I have always found this to be particularly odd as the living ghost has no entitlement to housing and if he/she has no access to employment or benefits how is he/she meant to survive?

I have to say however, that the people I know in this situation have never been involved with the criminal justice system, in fact they are terrified of the police. In their countries, if you get arrested, you are usually out cold by the time you reach the patrol car or dead.

Now you might wonder how the hell a person in this situation actually manages to survive? How do they eat? Where do they sleep? Do they sleep? What happens if they become ill? and please don't forget that many people seeking asylum in the UK have often fled their own countries in fear for their lives, they may have been detained & tortured, raped or lost family members as a result of war, the list is endless.

It shouldn't be so difficult to survive though should it? I mean, they take our jobs (err sorry! no permission to work!) our houses (oops! no permission to access housing) Oh yes!! lets not forget our women because we really have no independent thought processes do we?

Taking into account the atrocities that some of these people have endured in their lives, is it not suprising that people do not return 'voluntarily'?

Now in many cases, the Home Office http://www.ukba.homeoffice.gov.uk/ do not deport people back home, why? because their countries are known to be unsafe, it's just their accounts of what happened that weren't believed.
So when this happens they are left destitute and are living on our streets, in our democratic country in the 21st century how disgusting is that?

Welcome To The United Kingdom!



Where's my vote?

Where's my vote?
People just want the right to choose their own government

Man holds a picture of his murdered friend

Man holds a picture of his murdered friend
Killed for speaking out against the corrupt Ahmadinejad regime
STOP EXECUTIONS IN IRAN!

According to the United Nations Convention Against Torture 1984, Article I, the term "torture" means any act by which severe pain or suffering, whether physical or mental, is intentionally inflicted on a person for such purposes as obtaining from him or a third person information or a confession, punishing him for an act he or a third person has committed or is suspected of having committed, or intimidating or coercing him or a third person, or for any reason based on discrimination of any kind, when such pain or suffering is inflicted by or at the instigation of or with the consent or acquiescence of a public official or other person acting in an official capacity. It does not include pain or suffering arising only from, inherent in or incidental to lawful sanctions.Iran is not signatory of Convention Against Torture but it doesn't give Iranian government any right to torture Iranians.

Surely Things Aren't Really That Bad Are They? Come on, What's for Tea?

Now before you sit down and eat, I'd like you to try a little exercise, anyone can join in and it will only take about 10 minutes maximum. It doesn't matter who you are, whether you are a council worker, a politician, the Prime Minister, homeless, destitute it really does not matter.
Just close your eyes for a moment and imagine this.......

You live in a beautiful country, lets say Iran to keep it simple. Things are hard but your country is amazing, beautiful buildings, warmth, the smell of home cooking and incense wafting by as you relax after a day's hard work. You have always struggled, never really fitted in because your father is Iranian and your Mother Kurdish but nevertheless that's part of life and there are mixed race people everywhere.
Suddenly you are jolted from your relaxation by banging on your door so you rush to see what the problem is.
It must have only taken a few seconds to reach the door but when you get there you see your elderly father being taken by military police handcuffed with a gun to his head.
You stare in horror and then being the eldest son you need to make sure your mum & sister are ok.
In your mum's room you see her crying on the bed and just as you are walking over to her your sister screams so you rush to her room but one soldier is still there so you can't do a thing except witness her rape and torture that seems to last a lifetime. Your mum knows whats happened and she is praying that she will die. Imagine that!
Imagine this is the 5th, 6th 7th or 8th time this has happened?
Your father, well you never saw him again after the first time, your sister could face execution for having sex before marriage and now who will marry her anyway?
Your Mother well she still wants to die but can't quite get there & you! are meant to protect them but you know the interrogators will be back for you because your're half Kurdish and you support independence for Kurdish people and they really don't like that.
Imagine that!! so you flee to protect your own life and also you feel that it may be easier on your family if you aren't there.
You don't know where you will end up when you smuggle yourself onto lorries, boats e.t.c or even if you will get to the other end alive but you do it....you are amazing imagine that!

This exercise wasn't made up, it was based upon real life history. A close friend of mine who I will call S experienced this and more on a regular basis. S is a man who was detained, raped and tortured systematically by the Iranian regime. Other examples include.......

Thousands face mass eviction from homes and market stalls in Zimbabwe
Up to 200 people from an informal settlement in the Harare suburb of Gunhill in Zimbabwe face being forcibly evicted without being given adequate notice or any consultation or due process. Thousands of vendors across Harare also face forcible removal from their market stalls. The majority of those to be affected are poor women whose principal source of livelihood is selling fruits, vegetables and other wares at market stalls like Mbare Musika and Mupedzanhamo in Harare.The Deputy Mayor of the Harare City Council stated in July 2009 that the city authorities are considering evicting people from "illegal settlements and market places to restore order." He claimed that the targeted people pose a health hazard and violate the city's by-laws.
www.hrw.org/ (Human Rights Watch 2009)


Iranian girl prisoners systematically raped before execution
The Iranian practice of raping girl prisoners before execution has been reported previously, but perhaps never with such clear documentation. "Progressives" who support this regime should keep it in mind. It is unlikely that there will be any investigation by the UN or a human rights group.

Ami Isseroff

'I wed Iranian girls before execution'
Jul. 19, 2009SABINA AMIDI, Special to The Jerusalem Post , THE JERUSALEM POST
In a shocking and unprecedented interview, directly exposing the inhumanity of Supreme Leader Ali Khamenei's religious regime in Iran, a serving member of the paramilitary Basiji militia has told this reporter of his role in suppressing opposition street protests in recent weeks.
He has also detailed aspects of his earlier service in the force, including his enforced participation in the rape of young Iranian girls prior to their execution.
He said he had been a highly regarded member of the force, and had so "impressed my superiors" that, at 18, "I was given the 'honor' to temporarily marry young girls before they were sentenced to death."
In the Islamic Republic it is illegal to execute a young woman, regardless of her crime, if she is a virgin, he explained. Therefore a "wedding" ceremony is conducted the night before the execution: The young girl is forced to have sexual intercourse with a prison guard - essentially raped by her "husband."
"I regret that, even though the marriages were legal," he said.
Why the regret, if the marriages were "legal?"
"Because," he went on, "I could tell that the girls were more afraid of their 'wedding' night than of the execution that awaited them in the morning. And they would always fight back, so we would have to put sleeping pills in their food. By morning the girls would have an empty expression; it seemed like they were ready or wanted to die.
"I remember hearing them cry and scream after [the rape] was over," he said. "I will never forget how this one girl clawed at her own face and neck with her finger nails afterwards. She had deep scratches all over her."

Still hungry?

Oh Mr. Brown! (Gordon) you are an exception enjoy your tea!

(THIS IS THE UNITED KINGDOM)

The United Kingdom is a Country of Democracy, Equality and Values the Protection of Human Rights.

So you have arrived in the United Kingdom tired, hungry, traumatised and dehydrated but nevertheless grateful to be in a country where you know you will not be executed..(there's a good start).

Despite your frail state however you manage with the help of an interpreter to complete a lengthy document stating your claim for asylum and why you were forced to flee your beautiful country with the wonderful history and the smell of home cooking e.t.c. for a country you know absolutely nothing about....You are amazing!

Asylum is given under the 1951 United Nations Convention Relating to the Status of Refugees http://www.asylumrights.org.uk/convention.htm.

To be recognised as a refugee, you must have left your country and be unable to go back because you have a well-founded fear of persecution because of your:
.race;
.religion;
.nationality;
.political opinion; or
.membership of a particular social group.

In 2007, 19 out of every 100 people who applied for asylum were recognised as refugees and given asylum.

Eventually you are offered accommodation with the support of NASS National Asylum Support Service (NASS) just until a decision is made about whether you will be granted leave to remain in the United Kingdom. You are also provided with vouchers so that you can eat.
www.asylumsupport.info/nass.htm

Things seem to be a little easier now and you can relax and recover from your ordeal in the knowledge that you will be safe but you can't look for a job to support yourself or access a house independently not yet! not until you become a British Citizen so you'll just have to hope for the best for now and wait until you get your UK leave to remain.

This means that it will be almost impossible to learn English Language at the moment because you don't really have the chance to mix in with British people as most of them congregate in places like 'Workplaces' or 'Housing Communities' all the places you can't go.

I guess you could go to social places like clubs or pubs but you don't have any money to do that and they don't accept vouchers sorry! but I guess you have freedom of choice don't you?




Beyond What is Visible

You were once a stranger to me but now I know you,
Not all of you, that could never be
Always a part of you that no one will ever see, not even me.

Once a stranger with beautiful brown eyes, the most beautiful eyes I have ever seen,
Eyes that felt nothing, no emotion nothing in between, this life and beyond.

We were once strangers but then we touched,
Not in the way some might think, not too much.
The touch we shared was deep and true,
Not physical but you did touch me and I did touch you.

You were once a stranger to me but now I know you,
Not all of you, that could never be.
Sometimes there's a moment when your eyes melt me,
So warm and compassionate, oh such a change in time, or is it?
Maybe I was blind.

We dont have words but thats fine,
I don't speak your language and you don't speak mine
But when you touched me I understood what you needed to say, it just needed time.




The Decision.........Dont worry!! Help is at hand. This is the United Kingdom.

So today is the day! the letter has arrived and with anticipation you open it.
You don't understand.............
You told the truth, explained why you had to flee your country, about the rape the torture why have they refused your application?
Why?
Quickly you must try and lodge an appeal against this decision.
The Home Office have stated that certain things are untrue or overstated but you know you told the truth.

You admit and acknowledge that when you lodged your claim, you were traumatised, tired, hungry and dehydrated and had travelled for thousands of miles in appalling conditions but you told the truth.
So you lodge your appeal and this fails too so what now?

Another letter arrives... you breath a sigh of relief as this could be to say that they made a mistake, they were wrong but no, its from NASS to say that in 28 days you must leave your home and return voluntarily to your country as you are now not permitted to remain in the UK. In 28 days time your vouchers will cease also.

So far you have managed alone with your memories of what happened to you and your family, tormented and unable to sleep you have paced the floor, even turned to alcohol which in your country is prohibited but you coped now its different. Who can you turn to? where can you get help when you don't even speak English?
Maybe the nurse in the hospital will understand as you wake up with both your wrists bandaged.

Relax! This is the United Kingdom there is always a way forward.

In the UK there is something called Section 4 support

Section 4 support

Applying for support

This page explains how you may qualify for short-term support if your application for asylum was unsuccessful, you are unable to return to the country you came from and would otherwise be homeless or without the money to buy food (we call this 'destitute').
If your asylum application has been rejected, you must return to your country of origin as soon as possible. However, you may be able to receive short-term support while you are waiting to return to your country. This is known as section 4 support because it is given under the terms of section 4 of the Immigration and Asylum Act 1999.
There are strict requirements you must meet in order to qualify for section 4 support. You must be destitute and satisfy one of the following requirements:
you are taking all reasonable steps to leave the United Kingdom or placing yourself in a position where you can do so;
you are unable to leave the United Kingdom because of a physical barrier to travel or for some other medical reason;
you are unable to leave the United Kingdom because the UK Border Agency believes there is no safe route available;
you have either applied for a judicial review of your asylum application in Scotland or applied for a judicial review of your asylum application in England, Wales or Northern Ireland and been given permission to proceed with it; or
accommodation is necessary to prevent a breach of your rights, within the meaning of the Human Rights Act 1998.

http://www.ukba.homeoffice.gov.uk/asylum/support/apply/section4/

So What is Section 4 all about?

Now Section 4 of The Asylum and Immigration Act 1999 is a magical piece of legislation put in place by the Home Office to help you so please trust them and do not listen to anyone who tells you otherwise.

Yes thats right! The Home Office were the people who looked at your asylum claim and refused it.

Lets take a closer look at Section 4 and what you must do to get it....

1- You must be willing to leave the UK and you must be putting yourself in a position to do so.

Oh but wait! you came to the UK fleeing for your life so this wont work.

2-You cannot leave the UK because you are unable to travel due to physical barriers.

Hmmm at the moment you are not registered as having these kinds of problems and even if you had, who would be aware of it? You have no access to anything and in any case you can't speak English.

3- you are unable to leave the United Kingdom because the UK Border Agency believes there is no safe route available;

Well your asylum claim was refused so the Home Office obviously believe it is safe.

4-
you have either applied for a judicial review of your asylum application in Scotland or applied for a judicial review of your asylum application in England, Wales or Northern Ireland and been given permission to proceed

Your asylum claim and appeal was refused (Not doing too well here)

5-
accommodation is necessary to prevent a breach of your rights, within the meaning of the Human Rights Act 1998.

Damn!! They just took your accommodation.

On a positive note, your local authority (The city where you live) know about this so they should help shouldn't they?
Let's hear what they have to say,and what they are planning to do about it..............

Home
About MCC Manchester
MCC Manchester News
News, events and activities in the life of the Metropolitan Community Church, Manchester (UK).
May 30, 2009
Support for refused asylum seekersPosted by Steve Gray under Social action Tags: , , , , Leave a Comment

Refused asylum seekers left destitute in the UK
Background information

No doubt you will have heard or read reports about how the UK is meant to be a “soft touch” for asylum seekers. Yet, in reality, the level of support provided to asylum seekers is far lower than that of income support and is usually withdrawn altogether if a claim is refused.

Many refused asylum seekers are, in fact, unable to return to their home countries due to the risks they would face because of, for example, armed conflicts, generalised violence and repressive regimes. As a result, many refused asylum seekers from countries where such problems are rife (including Zimbabwe, Iran, Iraq, Sudan, Afghanistan, Somalia, the Democratic Republic of Congo and Eritrea) are being forced into destitution, as they are not permitted to work here.

To make matters worse, it appears as though this could be part of a deliberate strategy on the part of the UK Government. Certainly, this is the view of the Joint Committee on Human Rights, which recently reviewed the treatment of asylum seekers in the UK and reached the following conclusion:

“We have been persuaded by the evidence that the Government has indeed been practising a deliberate policy of destitution of this highly vulnerable group.

We believe that the deliberate use of inhumane treatment is unacceptable. We have seen instances in all cases where the Government’s treatment of asylum seekers and refused asylum seekers falls below the requirements of the common law of humanity and of international human rights law”.
In light of this, we are calling on you to support the Still Human Still Here Campaign, which is fully endorsed by Amnesty International and many other reputable organisations (http://stillhumanstillhere.wordpress.com/).

The Still Human Still Here Campaign is dedicated to highlighting the plight of tens of thousands of refused asylum seekers who are destitute in the UK.

Supporters of the campaign believe that the denial of any means of subsistence to refused asylum seekers as a matter of government policy is both inhumane and ineffective.
Its supporters are calling on the Government to:
End the threat and use of destitution as a tool of Government policy against refused asylum seekers

Continue financial support and accommodation to refused asylum seekers as provided during the asylum process and grant permission to work until such a time as they have left the UK or have been granted leave to remain

Continue to provide full access to health care and education throughout the same period

What can I do?

We are asking you to write to your local MP in order to highlight the issue and ask for his or her support. Please feel free to use the model letter below (preferably adapting it, where possible) for this purpose. If you don’t know who your

MP is, you can find out at http://www.theyworkforyou.com/.

Then, all you need to do is send your letter (addressed to your own MP) to:
House of CommonsLondonSW1 0AA
If you receive a reply from your MP, please send a copy to The Human Rights Action Centre, 17-25 New Inn Yard, London, EC2A 3EA

Well, they have been persuaded so theres a good thing, but it looks like they are going to do absolutely nothing!



Please Don't Be The Next Living Ghost

The inspiration for this blog has been given to me by some truly amazing people who I have been fortunate to meet along life's journey. Unfortunately, although it would be an honour to use their full titles I am only able to identify them by initials.
Some of the mentioned people have fled their countries in fear of their lives, and some sadly did not make it.

I would like to take this opportunity to thank these people from the bottom of my heart for allowing me to be a part of their journey and for being courageous enough to come forward with their stories.

I hope that after visiting my blog you will share some of your own experiences and be proactive in writing letters and doing whatever it takes to make changes to the current asylum laws.

This can be done, it just takes time and determination and most of all a willingness to stand in unity.

S.M -A courageous and amazing man of Kurdish-Iranian origin. Having experienced torture & detention for political reasons he fled to the UK in fear for his life. This man has diagnosed Post Traumatic Stress Disorder and needs close monitoring due to five previous and serious suicide attempts. Initial asylum claim failed and now in the process of appeal. If returned to Iran he faces definite execution.
This man lives in Manchester England.

S.G.T- A courageous and amazing man of Kurdish Iranian origin, having fled his country for political reasons he still awaiting the outcome of his asylum claim to remain in the UK. A member of the PKK (Kurdish Independence Party) he will definitely face execution by hanging if returned.
This man lives in Manchester England.

S.H - A courageous and amazing Iranian man who fled Iran following his relationship with a girl of Jewish origin. The Basij police cut her throat in front of him and beat him so badly that he sustained a 7" scar on his head from a machete type blade (His father was one of Basij). In the UK he became a 'living ghost' and eventually returned to Iran as he could take no more pain and hopelessness from his destitute situation. He was subsequently executed by hanging, accused of espionage.

A.A -An amazing and couragious man who fled his home country of Iran because of political reasons. He is currently destitute on the streets of Manchester UK having failed his asylum application and appeal. He is now a living ghost.

F.A -Also a courageous and amazing man from Iran who was picked up and detained following a protest in the UK against the Ahmadinejad regime in his home country in which his family are stuck. This man faces deportation back to Iran where he is likely to be executed as an opposer of the Ahmadinejad government.
This man lives in Manchester England

A.R.Z -A courageous and amazing man from Afghanistan currently in the UK.
This man has his leave to remain in the United Kingdom but is so mentally affected by the atrocities and torture he endured in his country, he is unable to ever feel safe. He is dependent upon opium and living in Manchester England

M.M- A courageous and amazing young man of Iranian origin. Having fled his country because of sexuality reasons he came to the UK.
Homosexuality in Iran is punishable by the death penalty and his partner was hung at the age of just 23yrs.
This man failed in his application for asylum and in his appeal against the decision. He is now a living ghost in Manchester England.

M. An amazing and courageous young man from Eritrea who fled to the UK in fear for his life after all his family, mother, father, 2 brothers and his baby sister were slaughtered in front of his eyes by militia.
He escaped by hiding in a cupboard. He is awaiting the outcome of his appeal for asylum in the UK. He currently resides in accommodation provided by NASS due to his young age.

A.S An amazing and courageous man from Iran who has been deeply affected by the aftermath of the Iran Iraq war in which he served as a soldier. This man has serious mental health problems and the need for counselling but cannot access it having no access to support after his asylum claim and appeal were refused in the UK. Recently he stitched his own mouth and went on hunger strike just so someone would listen. He lives in Manchester.

MB, An amazing and Courageous Angolan man who was detained in Yarl's Wood with his 13-year-old son, was found hanged in a stairwell on the morning of his 35th birthday.
M's last words to his son were 'be brave, work hard, do well at school'

EN, An amazing and Courageous 26-year-old Zimbabwean man who was found drowned after his asylum claim and appeal to remain in the UK had failed.

HN-An amazing and Courageous man from Iran who was found with a gunshot wound two weeks after his asylum claim was refused.
H, was homosexual and fled Iran in March 2000 after being imprisoned for three months for his sexuality and sought sanctuary in the UK. He feared being executed if he was returned to Iran - where homosexuality is a 'crime' punishable by death.


Please Check out the following links and make a difference: Additionally, please contact me at:
morgana.1@hotmail.co.uk


http://stllhumanstillhere.wordpress.com/
http://www.church-poverty.org.uk/campaigns/li..
http://www.irr.org.uk/2005/september/ha000021.html
http://www.redcross.org.uk/.
http://www.torturecare.org.uk./
http://www.refugee-action.org.uk/manchester.
http://www.sareli.org.uk./
http://www.samaritans.org./
http://www.woodstreetmission.org.uk./

http://www.qva.org.uk/

http://www.immigrationboards.com


Monday, 20 April 2020

Probing For XML Encryption Weaknesses In SAML With EsPReSSO

Security Assertion Markup Language (SAML) is an XML-based standard commonly used in Web Single Sign-On (SSO) [1]. In SAML, the confidentiality of transferred authentication statements against intermediaries can be provided using XML Encryption [2]. However, implementing XML Encryption in a secure way can be tricky and several attacks on XML Encryption have been identified in the past [3] [4]. Therefore, when auditing a SAML endpoint, one should always consider testing for vulnerabilities in the XML Encryption implementation.

This blog post introduces our latest addition to the SAML Attacker of our BurpSuite extension EsPReSSO: the Encryption Attack tab. The new tab allows for easy manipulation of the encrypted parts within intercepted SAML responses and can, therefore, be used to quickly assess whether the SAML endpoint is vulnerable against certain XML Encryption attacks.


Weaknesses of XML Encryption

Implementations of XML Encryption can be vulnerable to adaptive chosen ciphertext attacks. This is a class of attacks in which the attacker sends a sequence of manipulated ciphertexts to a decryption oracle as a way to gain information about the plaintext content.
Falsely implemented XML Encryption can be broken using:
  • an attack against the CBC-mode decryption (quite similar to a padding oracle attack) [3] or
  • a Bleichenbacher attack against the RSA-PKCS#1 encryption of the session key  [4].
SAML makes use of XML Encryption and its implementations could, therefore, also be vulnerable to these attacks.

XML Encryption in SAML

To support confidential transmission of sensitive data within the SAML Assertion, assertions can be encrypted using XML Encryption. An EncryptedAssertion is shown in the abridged example below.

<EncryptedAssertion>
  <EncryptedData>
    <EncryptionMethod Algorithm="http://www.w3.org/2001/04/xmlenc#aes128-cbc"/>
    <KeyInfo>
      <EncryptedKey>
        <EncryptionMethod Algorithm="http://www.w3.org/2001/04/xmlenc#rsa-1_5"/>
        <CipherData>
          <CipherValue>
            [...]
          </CipherValue>
        </CipherData>
      </EncryptedKey>
    </KeyInfo>
    <CipherData>
        <CipherValue>
          [...]
        </CipherValue>
    </CipherData>
  </EncryptedData>
</EncryptedAssertion>

The EncryptedAssertion contains an EncryptedData element, which in turn is the parent of the EncryptionMethod, KeyInfo, and CipherData elements.  SAML makes use of what is referred to as a hybrid encryption scheme. This is done using a session key which symmetrically encrypts the payload data (the example uses AES-128 in CBC mode), resulting in the ciphertext contained in the EncryptedAssertion/EncryptedData/CipherData/CipherValue child element. The session key itself is encrypted using an asymmetric encryption scheme. In our example, RSA-PKCS#1.5 encryption is used with the public key of the recipient, allowing the contents of the the EncryptedKey child element to be derived from the KeyInfo element. 

Encryption Attacker

Our BurpSuite extension EsPReSSO can help detect vulnerable implementations with the newly integrated Encryption Attacker within EsPReSSO's SAML module.

Once a SAML response which contains an EncryptedAssertion has been intercepted, open the SAML tab, select the Attacks pane, and choose Encryption from the dropdown menu. This works in Burp's Proxy, as well as in the Repeater tool, and is depicted below.
As sketched out above, the symmetric session key is encrypted using the recipient's public key. Since the key is public, anybody can use it to encrypt a selected symmetric key and submit a valid encryption of arbitrary messages to the recipient. This is incredibly helpful because it allows us to produce ciphertexts that decrypt the chosen plaintexts. To accomplish this, one can purposefully send invalidly padded messages, or messages containing invalid XML, as a method to trigger and analyze the different reactions of the decryption endpoint (i.e, turning the endpoint into a decryption oracle). To facilitate these investigations, the new Encryption Attacker makes this process dead simple.
The screenshot above shows the essential interface of the new encryption tab:
At the top, the certificate used to encrypt the symmetric session key can be pasted into the text field. This field will be pre-filled automatically if the intercepted SAML message includes a certificate in the KeyInfo child element of the EncryptedData element. The Update Certificate checkboxes above the text area can be used to include the certificate in the manipulated SAML message.
In the Symmetric Key text field, the hexadecimal value of the symmetric session key can be set. Choose the asymmetric algorithm from the dropdown menu and click Encrypt key -- this will update the corresponding KeyInfo elements of the intercepted SAML message. 

The payload in the text area labeled XML data can now be entered. Any update in the XML data field will also be reflected in the hexadecimal representation of the payload (found on right of the XML data field). Note that this is automatically padded to the blocklength required by the symmetric algorithm selected below. However, the payload and the padding can be manually adjusted in the hex editor field.

Eventually, click the Encrypt content button to generate the encrypted payload. This will apply the changes to the intercepted SAML message, and the manipulated message using Burp's Forward or Go button can now be forwarded, as usual.

Probing for Bleichenbacher Oracles

Bleichenbacher's attack against RSA-PKCS1 v1.5 encryption abuses the malleability of RSA to draw conclusions about the plaintext by multiplying the ciphertext with adaptively chosen values, and observing differences in the received responses. If the (error-) responses differ for valid and invalid PKCS1 v1.5 ciphertexts, Bleichenbachers' algorithm can be used to decrypt the ciphertext without knowing the private key [6].

To determine whether or not a SAML endpoint is vulnerable to Bleichenbacher's Attack, we simply need to check if we can distinguish those responses received when submitting ciphertexts that are decrypted into invalidly formatted PKCS1 v1.5 plaintexts, from the responses we receive when sending ciphertexts that are decrypted into validly formatted plaintexts. 

Recall that PKCS1 v1.5 mandates a certain format of the encrypted plaintext, namely a concatenation of a BlockType 00 02, a randomized PaddingString (PS) that includes no 00 bytes, a 00 (NULL-byte) as delimiter, and the actual plaintext message. The whole sequence should be equal in size to the modulus of the RSA key used. That is, given the byte length k of the RSA modulus and the message length |m|, PS has the length |PS| = k - 3 - |m|. Furthermore, PKCS1 v1.5 demands that |PS| to be at least eight bytes long [5]. 

In SAML, the recipient's public key is usually known because it is published in the metadata, or even included in the EncryptedAssertion. For this reason, we do not need to fiddle around with manipulated ciphertexts. Instead, we simply submit a validly formatted RSA-PKCS1 v1.5 encrypted message and an encrypted message which deciphers into an invalidly formatted plaintext. As an example, assume an RSA public key of 2048 bits which we want to use to encrypt a 16 byte session key `01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10` (hexadecimal representation). |PS|$ is $2048/8 - 3 - 16 = 237, so a valid PKCS1 v1.5 plaintext, ready to be encrypted using `AA` for all 237 padding bytes, could look like the listing shown below.

00 02 AA AA AA AA AA AA AA AA AA AA AA AA AA AA
AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA
AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA
AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA
AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA
AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA
AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA
AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA
AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA
AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA
AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA
AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA
AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA
AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA
AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA 00
01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10
In the Encryption attack pane of EsPReSSO, ensure that the correct public key certificate has been added to the Certificate field. Insert a valid plaintext, such as the one above, into the Symmetric Key field and select Plain RSA encryption from the Algorithm drop down menu. Click the Encrypt button to compute the RSA transformation and apply the new EncryptedKey element to the intercepted SAML message. Now, submit the message by clicking Burp's Go or Forward button and carefully inspect the response.

Next, repeat the steps outlined above, but this time submit an invalid PKCS1 v1.5 message. For example, consider using an invalid BlockType of `12 34` instead of `00 02`, or replace the `00` delimiter so that the decryptor is unable to determine the actual message after decrypting the ciphertext. If you are able to determine from the recieved responses whether or not the submitted ciphertext decrypted into a valid PKCS1 v1.5 formatted plaintext, chances are high that the decryptor can be used as a Bleichenbacher oracle. Don't forget to take into account the actual XML data, i.e., the assertion encrypted with the new session key; by submitting valid or invalid XML, or by removing signatures from the SAML message or the assertion you may increase your chances of detecting differences in the returned responses.

Probing for Oracles in CBC-Mode Decryption

Another known attack on XML Encryption is aimed at the Cipher Block Chaining (CBC) mode, which can be used with the block ciphers AES or 3DES [2]. The attack is described in detail in this referenced paper [3] and is quite similar to Padding-Oracle attacks on CBC mode; the malleability of CBC mode encryption enables the attacker to perform a bytewise, adaptive manipulation of the ciphertext blocks which are subsequently sent to the decryptor. In most cases, the manipulated ciphertext will not decrypt to valid XML and an error will be returned. Sometimes, however, the plaintext will be parsed as valid XML, in which cases an error is thrown later on at the application layer. The attacker observes the differences in the responses in order to turn the decryptor into a ciphertext validity oracle which can be used to break the encryption.  Due to some particularities of the XML format, this attack can be very efficient, enabling decryption with about 14 requests per byte, and it is even possible to fully automate the process [7].

In order to determine if a particular SAML service provider is vulnerable to this attack, we can avoid the cumbersome ciphertext manipulation, if we are in possession of the decryptor's public key:
In the Encryption Attacker tab of EsPReSSO, add the public key certificate to the Certificate field (if necessary) and insert a symmetric key of your own devising into the  Symmetric Key text field. Select an appropriate RSA encryption method and click the Encrypt button to apply the new EncryptedKey element to the original SAML message. 

An XML message can now be inserted into the XML data text field. Select a CBC mode encryption algorithm and click Encrypt to apply the changes. As in the example above, press Burp's Go or Forward button to send the message and carefully inspect the response. Try sending invalid XML, e.g., by not closing a tag or using the `&` character without a valid entity and keep an eye open for differences in the returned responses. To manipulate the padding, the text field on the right side shows the hexadecimal representation of the plaintext, including the CBC padding. If you send a single block and set the last byte, which indicates the padding length to the blocksize, i.e. 16 or 0x10 for AES, the ciphertext should decrypt into an empty string and is generally considered "valid" XML.

Please refer to the original paper for more details, tips, and tricks for performing the actual attack [3]. 

Summary

The new XML Encryption attacker included in EsPReSSO can help security auditors to quickly assess if a SAML endpoint is vulnerable to known attacks against XML Encryption. To this end, the decryptor's public key is used in order to send suitable test vectors that can be provided in plaintext. Ciphertext manipulation is, therefore, not required. The actual process of decrypting an intercepted SAML message is, however, considered out of scope and not implemented in EsPReSSO.

In case you wonder how XML Encryption can be used in a secure fashion, here are some considerations [6]:
  • Always use an authenticated encryption mode such as AES-GCM instead of the CBC-mode encryption.
  • Using RSA-PKCS1 v1.5 within XML Encryption is particularly difficult to do in a secure manner, and it is recommended to use RSA with Optimal Asymmetric Encryption Padding (OAEP) instead [2].
  • Apply a digital signature over the whole SAML response, and ensure it is properly validated before attempting to decrypt the assertion. This should thwart the attack as a manipulated response can be recognized as such and should be rejected.
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