#VU104939 Memory leak in Linux kernel - CVE-2025-21768

Vulnerability identifier: #VU104939

Vulnerability risk: Low

CVSSv4.0: 4.3 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2025-21768

CWE-ID: CWE-401

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 memory leak within the seg6_output_core() function in net/ipv6/seg6_iptunnel.c, within the rpl_output() function in net/ipv6/rpl_iptunnel.c. A local user can perform a denial of service (DoS) attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: 6.12, 6.12.1, 6.12.2, 6.12.3, 6.12.4, 6.12.5, 6.12.6, 6.12.7, 6.12.8, 6.12.9, 6.12.10, 6.12.11, 6.12.12, 6.12.13, 6.12.14, 6.12.15, 6.13, 6.13.1, 6.13.2, 6.13.3

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External links
https://git.kernel.org/stable/c/4c0f200c7d06fedddde82209c099014d63f4a6c0
https://git.kernel.org/stable/c/5ab11a4e219e93b8b31a27f8ec98d42afadd8b7a
https://git.kernel.org/stable/c/92191dd1073088753821b862b791dcc83e558e07
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.12.16
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.13.4
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.14

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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.