What is CVE-2026-42268?

CVE-2026-42268 is a high-severity vulnerability in Owasp Modsecurity, classified under Integer Underflow. CVSS score: 7.5/10. Published 2026-05-12.

How severe is CVE-2026-42268?

High severity. CVSS v3 base score is 7.5 out of 10.

Integer overflow in Owasp Modsecurity

CVE-2026-42268

ModSecurity is an open source, cross platform web application firewall (WAF) engine for Apache, IIS and Nginx. From 3.0.0 to before 3.0.15, there is an unhandled exception (std::out_of_range) caused by unsigned integer underflow in libmodsecurity3 if the user (administrator) uses a rule any of @verifySSN, @verifyCPF, or @verifySVNR. This vulnerability is fixed in 3.0.15.

Published 2026-05-12 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.005 (40.5th percentile), scored 2026-10-19.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 40th percentile — 40.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.004 · newest: 0.005 · change: +0.001

Affected products

Owasp Modsecurity
Owasp-Modsecurity Modsecurity — versions >= 3.0.0, < 3.0.15

Weakness classification (CWE)

References

github.com/owasp-modsecurity/ModSecurity/security/advisories/GHSA-vwr3-7x7g-7p9w (Exploit, Vendor Advisory)

Frequently asked questions

What is CVE-2026-42268?: CVE-2026-42268 is a high-severity vulnerability in Owasp Modsecurity, classified under Integer Underflow. CVSS score: 7.5/10. Published 2026-05-12.
How severe is CVE-2026-42268?: High severity. CVSS v3 base score is 7.5 out of 10.