#VU104950 Use-after-free in Linux kernel - CVE-2025-21764

Vulnerability identifier: #VU104950

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-2025-21764

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 ndisc_alloc_skb() function in net/ipv6/ndisc.c. A local user can escalate privileges on the system.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: 6.13, 6.13.1, 6.13.2, 6.13.3

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External links
https://git.kernel.org/stable/c/3c2d705f5adf5d860aaef90cb4211c0fde2ba66d
https://git.kernel.org/stable/c/628e6d18930bbd21f2d4562228afe27694f66da9
https://git.kernel.org/stable/c/9e0ec817eb41a55327a46cd3ce331a9868d60304
https://git.kernel.org/stable/c/bbec88e4108e8d6fb468d3817fa652140a44ff28
https://git.kernel.org/stable/c/cd1065f92eb7ff21b9ba5308a86f33d1670bf926
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.13.4

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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.