PT-2025-6059 · Linux+1 · Linux Kernel+1

Jann Horn · Published 2025-01-14 · Updated 2025-02-11 · CVE-2025-21686

Positive Technologies (AI Summary)

CVSS v2.0

4.6

Medium

Base vector

AV:L/AC:L/Au:S/C:N/I:N/A:C

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

Description The issue arises when IORING REGISTER CLONE BUFFERS is used to clone buffers from one uring instance to another, where the two instances use different memory managers (MMs) for accounting. If the first instance is closed before the second, the pinned memory counters for the second instance can be decremented incorrectly, leading to negative locked memory. This occurs because the pinned memory was originally accounted for through the first instance.

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

RCE

Weakness Enumeration

CWE-20

Related Identifiers

BDU:2025-02808

CVE-2025-21686

Affected Products

Astra Linux

Linux Kernel

References · 17

• https://osv.dev/vulnerability/UBUNTU-CVE-2025-21686 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2025-21686 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2025-21686 · Security Note
• https://ubuntu.com/security/CVE-2025-21686 · Vendor Advisory
• https://bdu.fstec.ru/vul/2025-02808 · Security Note
• https://cve.org/CVERecord?id=CVE-2025-21686 · Security Note
• https://osv.dev/vulnerability/CVE-2025-21686 · Vendor Advisory
• https://twitter.com/CVEnew/status/1888985564440899853 · Twitter Post
• https://lore.kernel.org/linux-cve-announce/2025021054-CVE-2025-21686-d416@gregkh · Note
• https://twitter.com/vuldb/status/1888992601212387759 · Twitter Post
• https://git.kernel.org/linus/19d340a2988d4f3e673cded9dde405d727d7e248 · Note
• https://git.kernel.org/stable/c/19d340a2988d4f3e673cded9dde405d727d7e248 · Note
• https://t.me/cvedetector/17574 · Telegram Post
• https://git.kernel.org/stable/c/efd96fbe23fa87de39116f632401f67b93be21ab · Note
• https://kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.12.12 · Note