CVE-2026-64525: xfrm: move policy_bydst RCU sync from per-netns .exit to .pre_exit

mediumCVSS 5.5CVE-2026-64525

CSIRTS triage

vendor: Linux product: KernelOther

What: This vulnerability involves moving the policy_bydst RCU sync from per-netns .exit to .pre_exit.
Who is affected: Deployments of the Linux kernel using xfrm are affected.
Urgency: Remediation is necessary to ensure proper synchronization, though exploitation is not confirmed.
Action: Apply the latest kernel patches that address this issue.

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 5.5
Published: 2026-07-14
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-64525

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-2026-645250.16% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 5% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-64525	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 xfrm

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.

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