#VU103513 NULL pointer dereference in Linux kernel - CVE-2025-21666

Vulnerability identifier: #VU103513

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-2025-21666

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 EXPORT_SYMBOL_GPL() and vsock_connectible_has_data() functions in net/vmw_vsock/af_vsock.c. A local user can perform a denial of service (DoS) attack.

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/91751e248256efc111e52e15115840c35d85abaf
https://git.kernel.org/stable/c/9e5fed46ccd2c34c5fa5a9c8825ce4823fdc853e
https://git.kernel.org/stable/c/b52e50dd4fabd12944172bd486a4f4853b7f74dd
https://git.kernel.org/stable/c/bc9c49341f9728c31fe248c5fbba32d2e81a092b
https://git.kernel.org/stable/c/c23d1d4f8efefb72258e9cedce29de10d057f8ca
https://git.kernel.org/stable/c/daeac89cdb03d30028186f5ff7dc26ec8fa843e7

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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.