Description of problem: When parsing a peer's supported HMAC authentication options in the sctp_auth_asoc_get_hmac() function, a malicious peer can craft their HMAC array in such a way as to cause memory corruption (out-of-bounds read followed by use of retrieved out-of-bounds data), which at the very least could cause a denial of service via kernel panic, and possibly worse. It appears this could be triggered remotely when connecting to a malicious peer, or locally by a user acting as both endpoints. In both cases, the "auth_enable" sysctl must be set in order to trigger the bug. References: http://marc.info/?l=oss-security&m=128619854321910&w=1 http://marc.info/?l=linux-kernel&m=128596992418814&w=2
Statement: Red Hat is aware of this issue and is tracking it via the following bug: https://bugzilla.redhat.com/CVE-2010-3705. This issue did not affect the version of Linux kernel as shipped with Red Hat Enterprise Linux 3 as it did not include support for SCTP. It did not affect Red Hat Enterprise Linux 4 and 5 as it did not include upstream commit 1f485649 that introduced the problem. Future kernel updates in Red Hat Enterprise MRG may address this flaw.
http://git.kernel.org/?p=linux/kernel/git/davem/net-2.6.git;a=commitdiff;h=51e97a12bef19b7e43199fc153cf9bd5f2140362
Acknowledgements: Red Hat would like to thank Dan Rosenberg for reporting this issue.
This issue has been addressed in following products: Red Hat Enterprise Linux 6 Via RHSA-2010:0842 https://rhn.redhat.com/errata/RHSA-2010-0842.html
This issue has been addressed in following products: MRG for RHEL-5 Via RHSA-2010:0958 https://rhn.redhat.com/errata/RHSA-2010-0958.html