RHEL 6 : kernel (RHSA-2016:2128) (Dirty COW)
High Nessus Plugin ID 94454
SynopsisThe remote Red Hat host is missing one or more security updates.
DescriptionAn update for kernel is now available for Red Hat Enterprise Linux 6.6 Extended Update Support.
Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.
The kernel packages contain the Linux kernel, the core of any Linux operating system.
Security Fix(es) :
* A flaw was found in the Linux kernel's keyring handling code: the key_reject_and_link() function could be forced to free an arbitrary memory block. An attacker could use this flaw to trigger a use-after-free condition on the system, potentially allowing for privilege escalation. (CVE-2016-4470, Important)
* A race condition was found in the way the Linux kernel's memory subsystem handled the copy-on-write (COW) breakage of private read-only memory mappings. 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. (CVE-2016-5195, Important)
Red Hat would like to thank Phil Oester for reporting CVE-2016-5195.
The CVE-2016-4470 issue was discovered by David Howells (Red Hat).
* This update fixes a tape write problem by fixing the use of the sas_is_tlr_enabled API in the mpt3sas driver. The driver now checks whether Transport Layer Recovery (TLR) is enabled before enabling the MPI2_SCSIIO_CONTROL_TLR_ON flag. (BZ#1372352)
SolutionUpdate the affected packages.