Description
ModSecurity is an open source, cross platform web application firewall (WAF) engine for Apache, IIS and Nginx. In versions 2.9.8 to before 2.9.11, an empty XML tag can cause a segmentation fault. If SecParseXmlIntoArgs is set to On or OnlyArgs, and the request type is application/xml, and at least one XML tag is empty (eg <foo></foo>), then a segmentation fault occurs. This issue has been patched in version 2.9.11. A workaround involves setting SecParseXmlIntoArgs to Off.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| owasp-modsecurity | ModSecurity | >= 2.9.8, < 2.9.11 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | modsecurity-apache | 2.9.11-1 | — |
| Debian 13 | modsecurity-apache | 2.9.11-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | modsecurity | No fix yet | — |
| Ubuntu 26.04 LTS | modsecurity | No fix yet | — |
| Ubuntu 25.10 | modsecurity | No fix yet | — |
| Ubuntu 24.04 LTS | modsecurity | No fix yet | — |
| Ubuntu 22.04 LTS | modsecurity | No fix yet | — |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | modsecurity | No fix yet | — |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | apache2-mod_security2 | 2.9.11-1.1 | openSUSE-SU-2025:15313-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | mod_security +1 | 2.9.11-1.amzn2023.0.1 | ALAS2023-2025-1139 |
| Amazon Linux 2 | mod_security +1 | 2.9.11-1.amzn2.0.1 | ALAS2-2025-2963 |
Advisories 4
- openSUSE-SU-2025:15313-1 apache2-mod_security2-2.9.11-1.1 on GA media SUSE / openSUSE Security Updates · Mar 23, 2026
- WID-SEC-2025-1441 OWASP ModSecurity: Schwachstelle ermöglicht Denial of Service BSI CERT-Bund (WID) · Aug 19, 2025
- ALAS2-2025-2963 Moderate: mod_security security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Aug 19, 2025
- ALAS2023-2025-1139 Moderate: mod_security security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Aug 18, 2025