Vulnerability identifier: #VU56393

Vulnerability risk: Low

CVSSv3.1:

CVE-ID: CVE-2021-3715

CWE-ID: CWE-416

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Linux kernel
Operating systems & Components / Operating system

Vendor: Linux Foundation

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

Linux kernel: 4.4.218 - 5.5.14

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CPE

• cpe:2.3:o:linux_foundation:linux_kernel:4.4.218:*:*:*:*:*:*:*

External links
http://bugzilla.redhat.com/show_bug.cgi?id=1993988

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Q & A

Can this vulnerability be exploited remotely?

Is there known malware, which exploits this vulnerability?