CVE-2026-52946: fs/fcntl: fix SOFTIRQ-unsafe lock order in fasync signaling

CSIRTS triage

What

The vulnerability involves fixing SOFTIRQ-unsafe lock order in fasync signaling.

Who is affected

Deployments using fs/fcntl may be affected.

Urgency

Remediation is medium urgency due to the severity rating of 5.9.

Action

Apply the necessary patches as they become available.

AI-assisted analysis generated from the source advisory — verify against the original.

Details

Source

Microsoft Security Response Center (INTL · vendor-psirt · site)

Severity

medium — CVSS 5.9

Published

2026-06-09

Exploitation

Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-52946

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

• Low exploitation riskCVE-2026-529460.61% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 45% of all scored CVEs.

Referenced CVEs

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

• high[UPDATE] [high] Linux Kernel: Multiple vulnerabilitiescert-bund

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