#VU90089 Use-after-free in Linux kernel - CVE-2021-47235

Vulnerability identifier: #VU90089

Vulnerability risk: Low

CVSSv4.0: 5.9 [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:U/U:Clear]

CVE-ID: CVE-2021-47235

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 within the ec_bhf_remove() function in drivers/net/ethernet/ec_bhf.c. A local user can escalate privileges on the system.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: All versions

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External links
https://git.kernel.org/stable/c/db2bc3cfd2bc01621014d4f17cdfc74611f339c8
https://git.kernel.org/stable/c/1cafc540b7bf1b6a5a77dc000205fe337ef6eba6
https://git.kernel.org/stable/c/b1ad283755095a4b9d1431aeb357d7df1a33d3bb
https://git.kernel.org/stable/c/0260916843cc74f3906acf8b6f256693e01530a2
https://git.kernel.org/stable/c/19f88ca68ccf8771276a606765239b167654f84a
https://git.kernel.org/stable/c/95deeb29d831e2fae608439e243e7a520611e7ea
https://git.kernel.org/stable/c/d11d79e52ba080ee567cb7d7eb42a5ade60a8130
https://git.kernel.org/stable/c/9cca0c2d70149160407bda9a9446ce0c29b6e6c6

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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.