CVE-2026-98258
Description
A flaw was found in the Linux kernel's POSIX CPU timer subsystem. A race condition can occur when modifying or deleting a timer concurrently with its expiration handling, allowing the timer to be freed while still queued on an active expiry list. A local user could exploit this use-after-free (UAF) flaw to cause a Denial of Service (DoS) via a system crash or potentially escalate privileges.
Statement
Red Hat has evaluated this issue as having a Moderate severity impact because successful exploitation requires an authenticated local user to win a tight race condition during timer operations. The issue affects core kernel timer handling on newer releases such as Red Hat Enterprise Linux 10, while earlier platforms like RHEL 8 and 9 do not include the problematic code. Although the resulting memory corruption can destabilize the system or allow elevated access, the high execution complexity limits overall risk.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7 | N/A | 7.8 |
| Attack Vector | Local | N/A | Local |
| Attack Complexity | High | N/A | Low |
| Privileges Required | Low | N/A | Low |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | High | N/A | High |
| Integrity Impact | High | N/A | High |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
cve.org: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
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