Home / vulnerabilities libtasn1 Heap Overflow
Posted on 01 May 2015
Source : packetstormsecurity.org Link
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@hboeck.de
GPG: BBB51E42
