Red Hat update for kernel

1) Privilege escalation

EUVDB-ID: #VU1039

Risk: Medium

CVSSv4.0: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Green]

CVE-ID: CVE-2016-5195

CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

Exploit availability: Yes

Description

The vulnerability allows a  local user to obtain elevated privileges on the target system.
The weakness is due to race condition in the kernel memory subsystem in the management of copy-on-write operations on read-only memory mappings that lets attackers to overwrite kernel memory and gain kernel-level privileges.
Successful exploitation of the vulnerability results in gaining of root privileges on the vulnerable system.

Note: the vulnerability was being actively exploited.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Red Hat Enterprise Linux for Power, little endian - Extended Update Support: 7.2 - 7.3

Red Hat Enterprise Linux EUS Compute Node: 7.2 - 7.3

Red Hat Enterprise Linux for Power, big endian - Extended Update Support: 7.2 - 7.3

Red Hat Enterprise Linux for IBM z Systems - Extended Update Support: 7.2 - 7.3

Red Hat Enterprise Linux Server - Extended Update Support: 7.2 - 7.3

Red Hat Enterprise Linux Server - TUS: 7.2 - 7.3

Red Hat Enterprise Linux Server - AUS: 7.2 - 7.3

kernel (Red Hat package): 3.10.0-123.1.2.el7 - 3.10.0-327.36.2.el7

Red Hat Enterprise Linux for Power, little endian: 7

Red Hat Enterprise Linux for Power, big endian: 7

Red Hat Enterprise Linux for IBM z Systems: 7

Red Hat Enterprise Linux for Scientific Computing: 7

Red Hat Enterprise Linux Desktop: 7

Red Hat Enterprise Linux Workstation: 7

Red Hat Enterprise Linux Server: 7

:

CPE2.3

• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_power_little_endian_-_extended_update_support:7.2:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_power_little_endian_-_extended_update_support:7.3:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_eus_compute_node:7.2:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_eus_compute_node:7.3:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_power_big_endian_-_extended_update_support:7.2:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_power_big_endian_-_extended_update_support:7.3:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_ibm_z_systems_-_extended_update_support:7.2:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_ibm_z_systems_-_extended_update_support:7.3:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_server_-_extended_update_support:7.2:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_server_-_extended_update_support:7.3:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_server_-_tus:7.2:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_server_-_aus:7.2:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:kernel_redhat_package:3.10.0-123.1.2.el7:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_power_little_endian:7:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_power_big_endian:7:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_ibm_z_systems:7:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_scientific_computing:7:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_desktop:7:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_workstation:7:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_server:7:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:::::*:*:*:*:*:*:*

External links

https://access.redhat.com/errata/RHSA-2016:2098

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

Yes. This vulnerability is being exploited in the wild.