CVE-2026-53264: net/sched: act_api: use RCU with deferred freeing for action lifecycle

highCVSS 7CVE-2026-53264

CSIRTS triage

Other

What: This vulnerability involves the use of RCU with deferred freeing for action lifecycle.
Who is affected: Deployments using the affected net/sched functionality.
Urgency: Remediation is urgent due to the high severity rating.
Action: Apply the latest patches to mitigate this issue.

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

Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: high — CVSS 7
Published: 2026-06-09
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-53264

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-2026-532640.13% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 3% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-53264	coverage & exploitation status	NVD · CVE.org

Recent advisories for net/sched

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-2026-46319: net/sched: act_ct: Only release RCU read lock after ct_ftmsrc · 2026-06-09
highCVE-2026-53011: net/sched: taprio: fix use-after-free in advance_sched() on schedule switchmsrc · 2026-06-09
mediumCVE-2026-52984: net/sched: netem: fix queue limit check to include reordered packetsmsrc · 2026-06-09
highCVE-2026-46331: net/sched: fix pedit partial COW leading to page cache corruptionmsrc · 2026-06-09
mediumCVE-2026-53080: net/sched: cls_fw: fix NULL dereference of "old" filters before change()msrc · 2026-06-09