#VU106736 NULL pointer dereference in Linux kernel - CVE-2025-21904

Vulnerability identifier: #VU106736

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-2025-21904

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 NULL pointer dereference within the drivers/net/caif/caif_virtio.c. A local user can perform a denial of service (DoS) attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: 5.4, 5.4.0, 5.4.0 rc6, 5.4.1, 5.4.2, 5.4.3, 5.4.4, 5.4.5, 5.4.6, 5.4.7, 5.4.8, 5.4.9, 5.4.10, 5.4.11, 5.4.12, 5.4.13, 5.4.14, 5.4.15, 5.4.16, 5.4.17, 5.4.18, 5.4.19, 5.4.20, 5.4.21, 5.4.22, 5.4.23, 5.4.24, 5.4.25, 5.4.26, 5.4.27, 5.4.28, 5.4.29, 5.4.30, 5.4.31, 5.4.32, 5.4.33, 5.4.34, 5.4.35, 5.4.36, 5.4.37, 5.4.38, 5.4.39, 5.4.40, 5.4.41, 5.4.42, 5.4.43, 5.4.44, 5.4.45, 5.4.46, 5.4.47, 5.4.48, 5.4.49, 5.4.50, 5.4.51, 5.4.52, 5.4.53, 5.4.54, 5.4.55, 5.4.56, 5.4.57, 5.4.58, 5.4.59, 5.4.60, 5.4.61, 5.4.62, 5.4.63, 5.4.64, 5.4.65, 5.4.66, 5.4.67, 5.4.68, 5.4.69, 5.4.70, 5.4.71, 5.4.72, 5.4.73, 5.4.74, 5.4.75, 5.4.76, 5.4.77, 5.4.78, 5.4.79, 5.4.80, 5.4.81, 5.4.82, 5.4.83, 5.4.84, 5.4.85, 5.4.86, 5.4.87, 5.4.88, 5.4.89, 5.4.90, 5.4.91, 5.4.92, 5.4.93, 5.4.94, 5.4.95, 5.4.96, 5.4.97, 5.4.98, 5.4.99, 5.4.100, 5.4.101, 5.4.102, 5.4.103, 5.4.104, 5.4.105, 5.4.106, 5.4.107, 5.4.108, 5.4.109, 5.4.110, 5.4.111, 5.4.112, 5.4.113, 5.4.114, 5.4.115, 5.4.116, 5.4.117, 5.4.118, 5.4.119, 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External links
https://git.kernel.org/stable/c/29e0cd296c87240278e2f7ea4cf3f496b60c03af
https://git.kernel.org/stable/c/56cddf71cce3b15b078e937fadab29962b6f6643
https://git.kernel.org/stable/c/597c27e5f04cb50e56cc9aeda75d3e42b6b89c3e
https://git.kernel.org/stable/c/7b5fe58959822e6cfa884327cabba6be3b01883d
https://git.kernel.org/stable/c/8e4e08ca4cc634b337bb74bc9a70758fdeda0bcb
https://git.kernel.org/stable/c/90d302619ee7ce5ed0c69c29c290bdccfde66418
https://git.kernel.org/stable/c/990fff6980d0c1693d60a812f58dbf93eab0473f
https://git.kernel.org/stable/c/a466fd7e9fafd975949e5945e2f70c33a94b1a70
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.235
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.15.179
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4.291
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.1.131
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.12.19
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.13.7
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.14
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.6.83

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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.