#VU91197 Buffer overflow in Linux kernel - CVE-2021-47496

Vulnerability identifier: #VU91197

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-2021-47496

CWE-ID: CWE-119

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 memory corruption within the tls_err_abort(), tls_tx_records(), tls_push_record(), tls_sw_recvmsg() and tls_sw_splice_read() functions in net/tls/tls_sw.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/e0cfd5159f314d6b304d030363650b06a2299cbb
https://git.kernel.org/stable/c/f3dec7e7ace38224f82cf83f0049159d067c2e19
https://git.kernel.org/stable/c/e41473543f75f7dbc5d605007e6f883f1bd13b9a
https://git.kernel.org/stable/c/da353fac65fede6b8b4cfe207f0d9408e3121105

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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.