CVE-2019-25043

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.2% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2021-05-06 · updated 2026-06-17
Weakness: CWE-755

Description

ModSecurity 3.x before 3.0.4 mishandles key-value pair parsing, as demonstrated by a "string index out of range" error and worker-process crash for a "Cookie: =abc" header.

Affected products

owasp-modsecurity ModSecurity: from 3.0.0 before 3.0.4 — fixed in 3.0.4

How to fix

Upgrade to a fixed version: owasp-modsecurity ModSecurity 3.0.4. Check the vendor advisory for mitigations.

References

https://github.com/SpiderLabs/ModSecurity/issues/2566
https://github.com/SpiderLabs/ModSecurity/issues/2566

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