Synopsis
Important: kernel-rt security and bug fix update
Type/Severity
Security Advisory: Important
Topic
An update for kernel-rt is now available for Red Hat Enterprise MRG 2.
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.
Description
The kernel-rt packages provide the Real Time Linux Kernel, which enables fine-tuning for systems with extremely high determinism requirements.
Security Fix(es):
- It was found that the packet_set_ring() function of the Linux kernel's networking implementation did not properly validate certain block-size data. A local attacker with CAP_NET_RAW capability could use this flaw to trigger a buffer overflow, resulting in the crash of the system. Due to the nature of the flaw, privilege escalation cannot be fully ruled out. (CVE-2017-7308, Important)
- Mounting a crafted EXT4 image read-only leads to an attacker controlled memory corruption and SLAB-Out-of-Bounds reads. (CVE-2016-10208, Moderate)
- A flaw was found in the Linux kernel's implementation of seq_file where a local attacker could manipulate memory in the put() function pointer. This could lead to memory corruption and possible privileged escalation. (CVE-2016-7910, Moderate)
- A vulnerability was found in the Linux kernel. An unprivileged local user could trigger oops in shash_async_export() by attempting to force the in-kernel hashing algorithms into decrypting an empty data set. (CVE-2016-8646, Moderate)
Red Hat would like to thank Igor Redko (Virtuozzo kernel team) for reporting CVE-2016-8646.
Bug Fix(es):
- The kernel-rt packages have been upgraded to the 3.10.0-514 source tree, which provides a number of bug fixes over the previous version. (BZ#1440807)
Solution
For details on how to apply this update, which includes the changes described in this advisory, refer to:
https://access.redhat.com/articles/11258
The system must be rebooted for this update to take effect.
Affected Products
Fixes
- BZ - 1388821 - CVE-2016-8646 kernel: Oops in shash_async_export()
- BZ - 1395190 - CVE-2016-10208 kernel: EXT4 memory corruption / SLAB out-of-bounds read
- BZ - 1399727 - CVE-2016-7910 kernel: Use after free in seq file
- BZ - 1437404 - CVE-2017-7308 kernel: net/packet: overflow in check for priv area size
- BZ - 1440807 - update the MRG 2.5.z 3.10 kernel-rt sources
CVEs
References
Vulmon