Bug 234806 (CVE-2008-3443)

Summary:	<dev-lang/ruby-1.8.6_p287 regex.c infinite loop (CVE-2008-3443)
Product:	Gentoo Security	Reporter:	Robert Buchholz (RETIRED) <rbu>
Component:	Vulnerabilities	Assignee:	Gentoo Security <security>
Status:	RESOLVED FIXED
Severity:	minor	CC:	ruby
Priority:	High
Version:	unspecified
Hardware:	All
OS:	Linux
URL:	http://www.milw0rm.com/exploits/6239
Whiteboard:	B3 [noglsa]
Package list:		Runtime testing required:	---

Description Robert Buchholz (RETIRED) gentoo-dev

2008-08-15 11:02:34 UTC

CVE-2008-3443 (http://nvd.nist.gov/nvd.cfm?cvename=CVE-2008-3443):
  The regular expression engine (regex.c) in Ruby 1.8.5 and earlier, 1.8.6
  through 1.8.6-p286, 1.8.7 through 1.8.7-p71, and 1.9 through r18423 allows
  remote attackers to cause a denial of service (infinite loop and crash) via
  multiple long requests to a Ruby socket, related to memory allocation
  failure, and as demonstrated against Webrick.

Comment 1 Robert Buchholz (RETIRED) gentoo-dev

2008-08-15 11:05:01 UTC

I am unsure whether this also affects 287, as the author of the advisory confirmed only 286. It contains a reproducer though.

Comment 2 Robert Buchholz (RETIRED) gentoo-dev

2008-08-15 14:14:50 UTC

Steven Christey pointed out:

Note the following DoS in the regular expression engine, which smells like
a NULL pointer dereference.  This appears to have been fixed in the latest
release.  A *likely* (but not provable) changelog entry for the fix is:
"regex.c (DOUBLE_STACK, re_compile_fastmap0, re_adjust_startpos),
(re_search, re_match_exec): check if failed to allocate memory."

- Steve

Comment 3 Hans de Graaff gentoo-dev

2008-08-16 14:15:46 UTC

(In reply to comment #1)
> I am unsure whether this also affects 287, as the author of the advisory
> confirmed only 286. It contains a reproducer though.

Running the reproduce script against a webrick server did suck up all available memory with p287 as well. A more decent server such as mongrel quickly noticed that something fishy was going on and aborted the test requests, so the bug may well be in webrick.

Comment 4 Pierre-Yves Rofes (RETIRED) gentoo-dev

2009-04-17 12:16:01 UTC

any news here?

Comment 5 Alex Legler (RETIRED) archtester

2009-08-28 08:44:32 UTC

Tried the exploit once more. It did cause Webrick to print the whole ~140MB worth of A's from the exploit to the terminal. Redirecting that to a file took away the terminal CPU load, Webrick itself returned to normal operation after the attack.

After reviewing the CVE and other Advisories, I deem this issue is fixed in the tree, all versions are stable and no vunlerable versions are left.

GLSA? no.

Comment 6 Stefan Behte (RETIRED) gentoo-dev

2009-09-14 22:06:42 UTC

I vote NO. Closing NOGLSA.