Vulnerability identifier: #VU70486

Vulnerability risk: Low

CVSSv3.1: 4.8 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2022-4129

CWE-ID: CWE-476

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 perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference error in the Linux kernel's Layer 2 Tunneling Protocol (L2TP). A missing lock when clearing sk_user_data can lead to a race condition and NULL pointer dereference. A local user could use this flaw to potentially crash the system causing a denial of service.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel:

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External links
http://lore.kernel.org/all/20221114191619.124659-1-jakub@cloudflare.com/t
http://lore.kernel.org/netdev/20221121085426.21315-1-jakub@cloudflare.com/t
http://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/7X5SPXMXXFANDASPCKER2JIQO2F3UHCP/
http://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/AM5KFIE6JNZXHBA5A2KYDZAT3MEX2B67/
http://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/JOKXNIM2R4FQCDRQV67UMAY6EBC72QFG/

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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.