CVE-2026-18917: Libvirt: integer overflow in nodegetfreepages rpc handler leading to heap buffer overflow

mediumCVSS 6.6CVE-2026-18917

CSIRTS triage

vendor: Libvirt product: Libvirt Memory corruption

What: An integer overflow in the nodegetfreepages RPC handler causes a heap buffer overflow.
Who is affected: Libvirt deployments accepting RPC calls to nodegetfreepages from local or remote callers.
Urgency: Medium severity with heap buffer overflow potential; patch promptly to prevent memory corruption.
Action: Update Libvirt to a version with the integer overflow fix in the RPC handler.

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 6.6
Published: 2026-08-11
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-18917

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-2026-189170.13% 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-2026-18917	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

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Recent advisories for Libvirt

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