CVE-2026-30923: CWE-125: Out-of-bounds Read in owasp-modsecurity ModSecurity
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.
AI Analysis
Technical Summary
ModSecurity is an open source WAF engine used with Apache, IIS, and Nginx. In libModSecurity3 versions before 3.0.15, a segmentation fault occurs due to an out-of-bounds read when the t:hexDecode transformation inspects a single-character query string parameter. This vulnerability (CWE-125) allows an attacker to crash worker processes, causing denial of service. The fault is resolved in version 3.0.15.
Potential Impact
Exploitation of this vulnerability causes worker process crashes leading to denial of service. Service disruption persists only while the attack is ongoing, as worker processes recover after the segfault. There is no indication of code execution or data breach. No known exploits are reported in the wild.
Mitigation Recommendations
A fix is available in libModSecurity3 version 3.0.15. Users should upgrade to this version or later to remediate the vulnerability. No other mitigation steps are indicated or required.
CVE-2026-30923: CWE-125: Out-of-bounds Read in owasp-modsecurity ModSecurity
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.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
ModSecurity is an open source WAF engine used with Apache, IIS, and Nginx. In libModSecurity3 versions before 3.0.15, a segmentation fault occurs due to an out-of-bounds read when the t:hexDecode transformation inspects a single-character query string parameter. This vulnerability (CWE-125) allows an attacker to crash worker processes, causing denial of service. The fault is resolved in version 3.0.15.
Potential Impact
Exploitation of this vulnerability causes worker process crashes leading to denial of service. Service disruption persists only while the attack is ongoing, as worker processes recover after the segfault. There is no indication of code execution or data breach. No known exploits are reported in the wild.
Mitigation Recommendations
A fix is available in libModSecurity3 version 3.0.15. Users should upgrade to this version or later to remediate the vulnerability. No other mitigation steps are indicated or required.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-03-07T16:40:05.884Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69fa3fb2cbff5d86101cd312
Added to database: 5/5/2026, 7:06:26 PM
Last enriched: 5/5/2026, 7:21:27 PM
Last updated: 5/5/2026, 8:08:46 PM
Views: 2
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