CVE-2026-53309 (CVSS 9.8)

Description

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 the valid range of qr_regions. The other loops in the same function correctly use '<'. Fix the loop condition to use '<' for consistency and correctness.

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CVSS v3.1 Score

9.8

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS — Exploit Prediction

0.0040

Probability of exploitation

0.33%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

References

Other References

https://git.kernel.org/stable/c/01b61e8dda9b0fdb0d4cda43de25f4e390554d7b https://git.kernel.org/stable/c/1fb7f356547d9688822315cd2b205ff0bd5429b4 https://git.kernel.org/stable/c/2a0673836f019e7c032acbf48d022d5ccf02a845 https://git.kernel.org/stable/c/426cd8eedac89b86148d4478990eeef16e8a2520 https://git.kernel.org/stable/c/760ab35040aca8399021fdb9ff1db1089feb7194 https://git.kernel.org/stable/c/819d8ebad3200a53de99bd7e297bc428e41ced54 https://git.kernel.org/stable/c/c60a2710b73838d250cda57344c049b89abc5d52 https://git.kernel.org/stable/c/d5403ae28085761d58b555645bc7d5feadb10073

Frequently Asked Questions

What is 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 the valid range of qr_regions. The other loops in the same function correctly use '<'. Fix the loop condition to use '<' for consistency and correctness. It has a CVSS v3.1 base score of 9.8 (CRITICAL).

How severe is CVE-2026-53309? +

CVE-2026-53309 has a CVSS v3.1 score of 9.8 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately. The EPSS score is 0.0040, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-53309? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

CVE-2026-53309