CVE-2026-64423: ipv4: igmp: remove multicast group from hash table on device destruction

highCVSS 7.8CVE-2026-64423

CSIRTS triage

vendor: Linux product: kernelOther

What: The IGMP multicast group is not removed from the hash table upon device destruction.
Who is affected: Deployments of the Linux kernel with IGMP support may be affected.
Urgency: Remediation is advisable to maintain proper network functionality, though exploitation is not currently known.
Action: Monitor for updates regarding 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: high — CVSS 7.8
Published: 2026-07-14
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-64423

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-2026-644230.13% 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-2026-64423	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

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

highCVE-2026-64423: In the Linux kernel, the following vulnerability has been resolved: ipv4: igmp: remove multica…nvd

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