CVE-2026-53043: ocfs2/dlm: validate qr_numregions in dlm_match_regions()

criticalCVSS 9.8CVE-2026-53043

CSIRTS triage

vendor: null product: nullOther

What: There is a critical vulnerability in the ocfs2/dlm component related to the validation of qr_numregions in the dlm_match_regions function.
Who is affected: Deployments using the ocfs2/dlm component are affected.
Urgency: Remediation is urgent due to the critical severity and potential for exploitation.
Action: Apply the latest patches to mitigate this vulnerability.

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: critical — CVSS 9.8
Published: 2026-06-09
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-53043

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-2026-530430.52% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 41% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-53043	coverage & exploitation status	NVD · CVE.org

Recent advisories for ocfs2/dlm

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.

criticalCVE-2026-53309: In the Linux kernel, the following vulnerability has been resolved: ocfs2/dlm: fix off-by-one …nvd · 2026-06-26
criticalCVE-2026-53309: ocfs2/dlm: fix off-by-one in dlm_match_regions() region comparisonmsrc · 2026-06-09