VULNERABILITY INTELLIGENCE

CVE-2026-30923

CVSS score7.5 HIGH

EPSS probability0.43%

CISA KEVNot currently listed

Published2026-05-05

Last modified2026-07-25

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

Description

ModSecurity is an open source, cross platform web application firewall (WAF) engine for Apache, IIS and Nginx. Libmodsecurity is one component of the ModSecurity v3 project. A segmentation fault occurs when a rule using the t:hexDecode transformation inspects a query string parameter containing a single character. An attacker can exploit this to crash worker processes, causing a denial of service. Service resumes once the attack stops as worker processes recover from the segfault. All versions before 3.0.15 of libModSecurity3 are affected. This has been patched in version 3.0.15.

Weakness classification

security-advisories@github.com: CWE-125

Primary references

security-advisories@github.com — Patch, Product
security-advisories@github.com — Exploit, Vendor Advisory
134c704f-9b21-4f2e-91b3-4a467353bcc0 — Exploit, Vendor Advisory