CVE-2026-52946

Description

A flaw was found in the Linux kernel. A lock order deadlock can occur in the send_sigio() and send_sigurg() functions when a process group receives a signal. This vulnerability, caused by an unsafe lock order during software interrupts (SOFTIRQ) in asynchronous I/O (fasync) signaling, could allow a remote attacker to trigger a system deadlock by sending specially crafted TCP URG packets. This can lead to a denial of service (DoS) condition, making the system unresponsive.

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 HatNVDcve.org
Base Score5.5N/A7.5
Attack VectorLocalN/ANetwork
Attack ComplexityLowN/ALow
Privileges RequiredLowN/ANone
User InteractionNoneN/ANone
ScopeUnchangedN/AUnchanged
ConfidentialityNoneN/ANone
Integrity ImpactNoneN/ANone
Availability ImpactHighN/AHigh

Vector

Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Understanding the Weakness (CWE)

Availability

Technical Impact: DoS: Resource Consumption (CPU); DoS: Resource Consumption (Other); DoS: Crash, Exit, or Restart

Each thread of execution will "hang" and prevent tasks from completing. In some cases, CPU consumption may occur if a lock check occurs in a tight loop.

Frequently Asked Questions

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