Description
An issue was discovered in OWASP ModSecurity Core Rule Set (CRS) 3.0.2. Use of X.Filename instead of X_Filename can bypass some PHP Script Uploads rules, because PHP automatically transforms dots into underscores in certain contexts where dots are invalid.
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-crs | 3.2.0-1 | — |
| Debian 13 | modsecurity-crs | 3.2.0-1 | — |
| Debian 12 | modsecurity-crs | 3.2.0-1 | — |
| Debian 10 | modsecurity-crs | 3.2.3-0+deb10u3 | DLA-3293-1 |
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 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | modsecurity | No fix yet | — |
| Ubuntu 18.04 LTS | modsecurity-crs | No fix yet | — |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | mod_security_crs | No fix yet | — |
Advisories 1
- DLA-3293-1 modsecurity-crs - security update Debian Security (DSA / DLA) · Mar 9, 2026