CVE-2026-64322: udf: validate sparing table length as an entry count, not a byte count

highCVSS 7.8CVE-2026-64322

CSIRTS triage

Other

What: This vulnerability relates to improper validation of sparing table length in the UDF filesystem.
Who is affected: Deployments using the UDF filesystem.
Urgency: Remediation is important to ensure filesystem integrity, with no current exploitation reported.
Action: Apply the patch for CVE-2026-64322.

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 7.8
Published: 2026-07-14
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-64322

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-2026-643220.16% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 6% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-64322	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

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

highCVE-2026-64322: In the Linux kernel, the following vulnerability has been resolved: udf: validate sparing tabl…nvd

Recent advisories for udf

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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