oss-security - Heap overflow / invalid read in Libtasn1 before 4.5 (TFPA 005/2015)

Follow @Openwall on Twitter for new release announcements and other news

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <20150430144642.54356798@pc1>
Date: Thu, 30 Apr 2015 14:46:42 +0200
From: Hanno Böck <hanno@...eck.de>
To: oss-security@...ts.openwall.com, fulldisclosure@...lists.org,
  cve-assign@...re.org
Subject: Heap overflow / invalid read in Libtasn1 before 4.5 (TFPA 005/2015)

https://blog.fuzzing-project.org/9-Heap-overflow-invalid-read-in-Libtasn1-TFPA-0052015.html

While fuzzing GnuTLS I discovered a malformed certificate input sample
that would cause a heap overflow read of 99 bytes in the DER decoding
functions of Libtasn1. The heap overflow happens in the function
_asn1_extract_der_octet().

This issue was reported to the Libtasn1 developer on 16th April. A fix
was committed on 20th April and is part of the Libtasn1 4.5 release.
This issue was found with american fuzzy lop and address sanitizer.

http://git.savannah.gnu.org/gitweb/?p=libtasn1.git;a=commitdiff;h=f979435823a02f842c41d49cd41cc81f25b5d677
Git commit / fix

https://lists.gnu.org/archive/html/help-libtasn1/2015-04/msg00000.html
Libtasn1 4.5 release notes

https://crashes.fuzzing-project.org/TFPA-2015-005-libtasn1-4.4-heap-overflow.crt
Sample malformed certificate exposing heap overflow (test with
certtool -i --inder --infile=[sample] and address sanitizer or
valgrind)

-- 
Hanno Böck
http://hboeck.de/

mail/jabber: hanno@...eck.de
GPG: BBB51E42

Content of type "application/pgp-signature" skipped

Please check out the Open Source Software Security Wiki, which is counterpart to this mailing list.

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.