PT-2025-4322 · Linux · Linux Kernel

Published 2025-01-08 · Updated 2025-01-21 · CVE-2025-21641

Positive Technologies (AI Summary)

CVSS v3.1

5.5

Medium

Base vector

AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description The issue concerns the Linux kernel, specifically the mptcp subsystem and its handling of the blackhole timeout via sysctl. The problem arises from using the net structure via current, which is not recommended due to inconsistency and potential null pointer dereferences. This can lead to errors, particularly when the current task is exiting. The pernet structure can be obtained from the table->data using container of().

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Exploit

NULL Pointer Dereference

Weakness Enumeration

CWE-476

Related Identifiers

BDU:2025-15887

CVE-2025-21641

Affected Products

Linux Kernel

References · 22

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/21xxx/CVE-2025-21641.json · Exploit
• https://git.kernel.org/stable/c/4c74fbdc5ab95b13945be01e6065940b68222db7 · Patch
• https://ubuntu.com/security/CVE-2025-21641 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2025-21641 · Vendor Advisory
• https://linux.oracle.com/errata/ELSA-2025-20480.html · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2025-21641 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2025-21641 · Security Note
• https://bdu.fstec.ru/vul/2025-15887 · Security Note
• https://linux.oracle.com/errata/ELSA-2025-20530.html · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2025-21641 · Security Note
• https://osv.dev/vulnerability/BELL-CVE-2025-21641 · Vendor Advisory
• https://git.kernel.org/stable/c/92cf7a51bdae24a32c592adcdd59a773ae149289 · Patch
• https://osv.dev/vulnerability/UBUNTU-CVE-2025-21641 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2025-21641 · Vendor Advisory
• https://docs.bell-sw.com/security/cves/CVE-2025-21641 · Note