640339 - (CVE-2011-1202) generate-id() function leaks information about valid heap addresses

Status: RESOLVED FIXED

(Core :: XSLT, defect)

Description

[Daniel Veditz [:dveditz]]

As demonstrated at the test URL and announced on Chris Evans' blog the XPath generate-id() function returns a valid heap address which might provide a useful handle in other attacks. Appears to affect all browsers one way or another (Chrome was patched before announcing this).

http://scarybeastsecurity.blogspot.com/2011/03/multi-browser-heap-address-leak-in-xslt.html

Comment 1

[Jonas Sicking (:sicking) No longer reading bugmail consistently]

Attachment: patch to fix

Needs a bit more testing, but I think this should do it. I originally used the address of the txExecutionState itself, but since that usually lives on the stack it's possible that that'll be on a predictable address.

Comment 2

[Peter Van der Beken [:peterv]]

Comment on attachment 518223 [details] [diff] [review]
patch to fix

>diff --git a/content/xslt/src/xpath/txMozillaXPathTreeWalker.cpp b/content/xslt/src/xpath/txMozillaXPathTreeWalker.cpp

>+    PRUword nodeid = ((PRUword)aNode.mNode) - ((PRUword)aBase.mNode);

Don't think you need all those brackets.

>diff --git a/content/xslt/src/xslt/txGenerateIdFunctionCall.cpp b/content/xslt/src/xslt/txGenerateIdFunctionCall.cpp

>+            "called xslt extension function \"current\" with wrong context");

s/current/generate-id/

I don't think this can leak info about adresses anymore.

Comment 3

[Jonas Sicking (:sicking) No longer reading bugmail consistently]

Dan, I don't know how you want to do about landing this on branches given that I don't think it can land on trunk right now.

Comment 4

[Daniel Veditz [:dveditz]]

Comment on attachment 518223 [details] [diff] [review]
patch to fix

Approved for 1.9.2.16 and 1.9.1.18, a=dveditz for release-drivers

Comment 5

[Daniel Veditz [:dveditz]]

S'ok, we'll take the branches now and 4.0.1 when we can.

Comment 6

[Jonas Sicking (:sicking) No longer reading bugmail consistently]

Checked in to branches:

http://hg.mozilla.org/releases/mozilla-1.9.1/rev/768b54fa2f7d
http://hg.mozilla.org/releases/mozilla-1.9.2/rev/a201c429788b

Leaving open as it hasn't been check in to trunk yet.

Also nominating for the 2.0 branch as that'll likely be a separate landing.

Comment 7

[Daniel Veditz [:dveditz]]

Comment on attachment 518223 [details] [diff] [review]
patch to fix

Approved for the mozilla2.0 repository, a=dveditz for release-drivers

Comment 8

[Jonas Sicking (:sicking) No longer reading bugmail consistently]

Checked in on m-c and 2.0:

http://hg.mozilla.org/mozilla-central/rev/c2bd5cf4070e
http://hg.mozilla.org/releases/mozilla-2.0/rev/e01dc3fc20d3

Comment 10

[[e-mail]]

Attachment: patch security

Comment 11

[Jonas Sicking (:sicking) No longer reading bugmail consistently]

Tarak, what is this attachment supposed to be? It looks like an executable.

Comment 12

[Jonas Sicking (:sicking) No longer reading bugmail consistently]

Comment on attachment 529326 [details] [diff] [review]
patch security

Marking obsolete for now as I suspect this was added by mistake.