PT-2025-40637 · Linux · Linux Kernel

Published 2025-10-04 · Updated 2025-10-04 · CVE-2025-39941

Positive Technologies (AI Summary)

CVSS v3.1

4.7

Medium

Base vector

AV:L/AC:H/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 race condition exists in zram related to concurrent writes to the same zram index. This can lead to leaked zsmalloc handles. The issue occurs when multiple CPUs attempt to free memory (zs free()) before a new handle is properly set, potentially causing memory leaks. The vulnerability arises from performing zs free() too early in the process, before resetting the zram entry under the same slot lock scope. The affected code involves functions such as zram slot lock(), zs malloc(), and zram set handle().

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

Exploit

Race Condition

Weakness Enumeration

CWE-362

Related Identifiers

CVE-2025-39941

Affected Products

Linux Kernel

References · 14

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/39xxx/CVE-2025-39941.json · Exploit
• https://cve.org/CVERecord?id=CVE-2025-39941 · Security Note
• https://git.kernel.org/stable/c/ce4be9e4307c5a60701ff6e0cafa74caffdc54ce · Patch
• https://security-tracker.debian.org/tracker/CVE-2025-39941 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2025-39941 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2025-39941 · Vendor Advisory
• https://ubuntu.com/security/CVE-2025-39941 · Vendor Advisory
• https://git.kernel.org/stable/c/ff750e9f2c4d63854c33967d1646b5e89a9a19a2 · Patch
• https://nvd.nist.gov/vuln/detail/CVE-2025-39941 · Security Note
• https://osv.dev/vulnerability/UBUNTU-CVE-2025-39941 · Vendor Advisory
• https://twitter.com/CVEnew/status/1974378037451149325 · Twitter Post
• https://git.kernel.org/linus/ce4be9e4307c5a60701ff6e0cafa74caffdc54ce · Note
• https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git · Note
• https://t.me/CVEtracker/34103 · Telegram Post