PT-2025-14278 · Linux+2 · Linux Kernel+2

Published 2025-02-25 · Updated 2026-01-20 · CVE-2025-21897

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 A vulnerability in the Linux kernel has been resolved, related to the pick task scx() function picking non-queued tasks when called without balance(). The issue arises from a fair class bug where pick taks fair() may return NULL after a true return from balance fair(). This could lead to a non-runnable task being returned, causing failures and potential deadlocks. The estimated number of potentially affected devices worldwide is not available.

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

Exploit

Improper Locking

Weakness Enumeration

CWE-833

CWE-667

Related Identifiers

BDU:2025-04411

CVE-2025-21897

Affected Products

Astra Linux

Linux Kernel

Red Os

References · 24

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/21xxx/CVE-2025-21897.json · Exploit
• http://repo.red-soft.ru/redos/8.0/x86_64/updates · Vendor Advisory
• https://git.kernel.org/stable/c/8fef0a3b17bb258130a4fcbcb5addf94b25e9ec5 · Patch
• https://linux.oracle.com/errata/ELSA-2025-20480.html · Vendor Advisory
• https://osv.dev/vulnerability/UBUNTU-CVE-2025-21897 · Vendor Advisory
• https://bdu.fstec.ru/vul/2025-04411 · Security Note
• https://osv.dev/vulnerability/CVE-2025-21897 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2025-21897 · Security Note
• https://git.kernel.org/stable/c/5324c459f90d16b0c43a78b494c598915d782b7a · Patch
• https://git.kernel.org/stable/c/de60a31cb0bcacfaf9487546eac5e70e0a9c66d7 · Patch
• https://cve.org/CVERecord?id=CVE-2025-21897 · Security Note
• https://osv.dev/vulnerability/BELL-CVE-2025-21897 · Vendor Advisory
• https://linux.oracle.com/errata/ELSA-2025-20530.html · Vendor Advisory
• https://ubuntu.com/security/CVE-2025-21897 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2025-21897 · Vendor Advisory