CVE-2026-74594: sched/psi: Shut down rtpoll_timer in psi_cgroup_free()

mediumCVSS 4.7CVE-2026-74594

CSIRTS triage

vendor: Linux product: Linux Kernel Denial of service

What: The PSI rtpoll_timer is not properly shut down when a cgroup is freed, potentially causing resource leaks or use-after-free conditions.
Who is affected: Systems with PSI (Pressure Stall Information) enabled and active cgroup management.
Urgency: Medium priority; unpatched kernels may experience stability issues under cgroup-heavy workloads.
Action: Apply kernel patches addressing CVE-2026-74594 when available through distribution updates.

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

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Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: medium — CVSS 4.7
Published: 2026-08-11
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-74594

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-2026-745940.13% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 3% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-74594	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

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

Recent advisories for sched/psi

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

highCVE-2026-74594: In the Linux kernel, the following vulnerability has been resolved: sched/psi: Shut down rtpol…nvd · 2026-08-22
criticalCVE-2026-52991: sched/psi: fix race between file release and pressure writemsrc · 2026-06-09