How severe is CVE-2026-42268?

CVE-2026-42268 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-42268 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-42268?

CVE-2026-42268 affects Owasp Modsecurity. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-42268?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-42268 have an EU (EUVD) identifier?

Yes. CVE-2026-42268 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-29854.

When was CVE-2026-42268 published?

CVE-2026-42268 was published on 2026-05-12 and last updated on 2026-06-17.

CVE-2026-42268

CVE-2026-42268 is a high-severity vulnerability in Owasp Modsecurity with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-191.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v4: 8.2
EPSS exploit prediction: 0% (32nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-29854
Weakness: CWE-191
Affected product: Owasp Modsecurity
Published: 2026-05-12
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is 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.
How severe is CVE-2026-42268?: CVE-2026-42268 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-42268 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-42268?: CVE-2026-42268 affects Owasp Modsecurity. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-42268?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-42268 have an EU (EUVD) identifier?: Yes. CVE-2026-42268 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-29854.
When was CVE-2026-42268 published?: CVE-2026-42268 was published on 2026-05-12 and last updated on 2026-06-17.

References

https://github.com/owasp-modsecurity/ModSecurity/security/advisories/GHSA-vwr3-7x7g-7p9w

Affected products (1)

cpe:2.3:a:owasp:modsecurity:*:*:*:*:*:*:*:*

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