#VU90053 Use-after-free in Linux kernel - CVE-2021-47517

Vulnerability identifier: #VU90053

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-2021-47517

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 ethnl_ops_begin() function in net/ethtool/netlink.h. 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
http://git.kernel.org/stable/c/7c26da3be1e9843a15b5318f90db8a564479d2ac
http://git.kernel.org/stable/c/cfd719f04267108f5f5bf802b9d7de69e99a99f9
http://git.kernel.org/stable/c/dde91ccfa25fd58f64c397d91b81a4b393100ffa

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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.