A security regression (CVE-2006-5051) was discovered in OpenSSH's server (sshd). There is a race condition which can lead sshd to handle some signals in an unsafe manner. An unauthenticated, remote attacker may be able to trigger it by failing to authenticate within a set time period.

A buffer overflow was discovered in the GNU C Library's dynamic loader ld.so while processing the GLIBCTUNABLES environment variable. This issue could allow a local attacker to use maliciously crafted GLIBCTUNABLES environment variables when launching binaries with SUID permission to execute code with elevated privileges.

A heap-based buffer overflow was found in the way sudo parses command line arguments.

As per the researcher this vulnerability:

- is exploitable by any local user (normal users and system users, sudoers and non-sudoers), without authentication (i.e., the attacker does not need to know the user's password);

- was introduced in July 2011 (commit 8255ed69), and affects all legacy versions from 1.8.2 to 1.8.31p2 and all stable versions from 1.9.0 to 1.9.5p1, in their default configuration.

This could lead to privilege escalation.

A race condition was found in the way Linux kernel's memory subsystem handled breakage of the read only private mappings COW situation on write access.

An unprivileged local user could use this flaw to gain write access to otherwise read only memory mappings and thus increase their privileges on the system.

Red Hat is aware of this issue and if you have questions about the affectedness of your system please contact Red Hat Support. For additional information see https://access.redhat.com/security/vulnerabilities/2706661