#VU104944 Use-after-free in Linux kernel - CVE-2025-21753

Vulnerability identifier: #VU104944

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-2025-21753

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 fs/btrfs/transaction.c. A local user can escalate privileges on the system.

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/6ba4663ada6c6315af23a6669d386146634808ec
https://git.kernel.org/stable/c/86d71a026a7f63da905db9add845c8ee88801eca
https://git.kernel.org/stable/c/8f5cff471039caa2b088060c074c2bf2081bcb01
https://git.kernel.org/stable/c/ce628048390dad80320d5a1f74de6ca1e1be91e7
https://git.kernel.org/stable/c/e2f0943cf37305dbdeaf9846e3c941451bcdef63

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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.