A stack-based buffer overflow was found in libresolv when invoked from nssdns, allowing specially crafted DNS responses to seize control of EIP in the DNS client.

The buffer overflow occurs in the functions senddg (send datagram) and sendvc (send TCP) for the NSS module libnssdns.so.2 when calling getaddrinfo with AFUNSPEC family, or in some cases AFINET6 family. The use of AFUNSPEC (or AFINET6 in some cases) triggers the low-level resolver code to send out two parallel queries for A and AAAA. A mismanagement of the buffers used for those queries could result in the response of a query writing beyond the alloca allocated buffer created by resnquery.

HPE Insight Control before 7.5.1 allow remote attackers to obtain sensitive information, modify data, or cause a denial of service via unspecified vectors.

It was reported that possible use-after-free vulnerability in keyring facility, possibly leading to local privilege escalation, was found. Function joinsessionkeyring in security/keys/processkeys.c holds a reference to the requested keyring, but if that keyring is the same as the one being currently used by the process, the kernel wouldn't decrease keyring->usage before returning to userspace. The usage field can be possibly overflowed causing use-after-free on the keyring object.

Introduced by: http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=3a50597de8635cd05133bd12c95681c82fe7b878

References: http://perception-point.io/2016/01/14/analysis-and-exploitation-of-a-linux-kernel-vulnerability-cve-2016-0728/

Red Hat KCS article: https://access.redhat.com/articles/2131021

Upstream patch: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=23567fd052a9abb6d67fe8e7a9ccdd9800a540f2