Red Hat Enterprise Linux 7 update for kernel-rt

Published: 2021-09-09

Risk	Low
Patch available	YES
Number of vulnerabilities	1
CVE-ID	CVE-2021-3715
CWE-ID	CWE-416
Exploitation vector	Local
Public exploit	N/A
Vulnerable software Subscribe	kernel-rt (Red Hat package) Operating systems & Components / Operating system package or component Red Hat Enterprise Linux for Real Time Operating systems & Components / Operating system Red Hat Enterprise Linux for Real Time for NFV Operating systems & Components / Operating system
Vendor	Red Hat Inc.

Security Bulletin

This security bulletin contains one low risk vulnerability.

1) Use-after-free

EUVDB-ID: #VU56393

Risk: Low

CVSSv3.1:

CVE-ID: CVE-2021-3715

CWE-ID: CWE-416 - Use After Free

Exploit availability: No

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a use-after-free error in the "Routing decision" classifier in the Linux kernel's Traffic Control networking subsystem (route4_change() function in net/sched/cls_route.c) in the way it handled changing of classification filters. A local user can trigger a use-after-free error and execute arbitrary code with elevated privileges.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

kernel-rt (Red Hat package): 3.10.0-229.1.2.rt56.141.2.el7_1 - 3.10.0-1160.41.1.rt56.1181.el7

Red Hat Enterprise Linux for Real Time: 7 - 7

Red Hat Enterprise Linux for Real Time for NFV: 7 - 7

CPE2.3

cpe:2.3:o:red_hat:kernel-rt:3.10.0-1160.41.1.rt56.1181.el7:*:*:*:*:red_hat_enterprise_linux:*:*

External links

http://access.redhat.com/errata/RHSA-2021:3439

Q & A

Can this vulnerability be exploited remotely?

Is there known malware, which exploits this vulnerability?