What is CVE-2026-53309?

CVE-2026-53309 is a critical-severity vulnerability in Linux, classified under Off-by-one Error. CVSS score: 9.8/10. Published 2026-06-26.

How severe is CVE-2026-53309?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Vulnerability in Linux

CVE-2026-53309

In the Linux kernel, the following vulnerability has been resolved: ocfs2/dlm: fix off-by-one in dlm_match_regions() region comparison The local-vs-remote region comparison loop uses '<=' instead of '<', causing it to read one entry past…

EPSS: 0.004 (32.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Linux — versions ea2034416b54700e30371f2ad6517cbb94674083, 2.6.37, 0
Linux Linux_kernel

Weakness classification (CWE)

CWE-193 — Off-by-one Error

References

416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)

Frequently asked questions

What is CVE-2026-53309?: CVE-2026-53309 is a critical-severity vulnerability in Linux, classified under Off-by-one Error. CVSS score: 9.8/10. Published 2026-06-26.
How severe is CVE-2026-53309?: Critical severity. CVSS v3 base score is 9.8 out of 10.