#VU105659 NULL pointer dereference in Linux kernel - CVE-2025-21844

Vulnerability identifier: #VU105659

Vulnerability risk: Low

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

CVE-ID: CVE-2025-21844

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 fs/smb/client/smb2ops.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
http://git.kernel.org/stable/c/24e8e4523d3071bc5143b0db9127d511489f7b3b
http://git.kernel.org/stable/c/554736b583f529ee159aa95af9a0cbc12b5ffc96
http://git.kernel.org/stable/c/860ca5e50f73c2a1cef7eefc9d39d04e275417f7
http://git.kernel.org/stable/c/9e5d99a4cf2e23c716b44862975548415fae5391
http://git.kernel.org/stable/c/a9b0b4b29877cb4dc5d0842b59b5ccbacddb85bd

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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.