Red Hat Enterprise Linux 6 update for kernel

1) Data handling

EUVDB-ID: #VU3800

Risk: Low

CVSSv4.0: 4.3 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2016-4470

CWE-ID: CWE-19 - Data Handling

Exploit availability: No

Description

The vulnerability allows a local attacker to cause DoS condition on the target system.

The weakness exists in the key_reject_and_link function in security/keys/key.c due to it does not ensure that a certain data structure is initialized. A local attacker can cause the service to crash via vectors involving a crafted keyctl request2 command.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Red Hat Enterprise Linux Server - AUS: 6.4

kernel (Red Hat package): before 2.6.32-358.75.1.el6

CPE2.3

• cpe:2.3:o:red_hat:red_hat_enterprise_linux_server_-_aus:6.4:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:a:red_hat:kernel_redhat_package:*:*:*:*:*:red_hat_enterprise_linux:*:*

External links

https://access.redhat.com/errata/RHSA-2016:2133

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?

No. We are not aware of malware exploiting this vulnerability.

2) 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 Server - AUS: 6.4

kernel (Red Hat package): before 2.6.32-358.75.1.el6

CPE2.3

• cpe:2.3:o:red_hat:red_hat_enterprise_linux_server_-_aus:6.4:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:a:red_hat:kernel_redhat_package:*:*:*:*:*:red_hat_enterprise_linux:*:*

External links

https://access.redhat.com/errata/RHSA-2016:2133

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.