| Name | CVE-2022-39956 |
| Description | The OWASP ModSecurity Core Rule Set (CRS) is affected by a partial rule set bypass for HTTP multipart requests by submitting a payload that uses a character encoding scheme via the Content-Type or the deprecated Content-Transfer-Encoding multipart MIME header fields that will not be decoded and inspected by the web application firewall engine and the rule set. The multipart payload will therefore bypass detection. A vulnerable backend that supports these encoding schemes can potentially be exploited. The legacy CRS versions 3.0.x and 3.1.x are affected, as well as the currently supported versions 3.2.1 and 3.3.2. Integrators and users are advised upgrade to 3.2.2 and 3.3.3 respectively. The mitigation against these vulnerabilities depends on the installation of the latest ModSecurity version (v2.9.6 / v3.0.8). |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| References | DLA-3293-1, ELA-783-1 |
| Debian Bugs | 1021137 |
Vulnerable and fixed packages
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|
| modsecurity-crs (PTS) | jessie | 2.2.9-1+deb8u1 | vulnerable |
| stretch (lts), stretch | 3.2.3-0+deb9u1 | fixed |
| buster (security), buster, buster (lts) | 3.2.3-0+deb10u3 | fixed |
| bullseye | 3.3.0-1+deb11u1 | vulnerable |
| bookworm | 3.3.4-1 | fixed |
| sid, trixie | 3.3.7-1 | fixed |
The information below is based on the following data on fixed versions.
Notes
[bullseye] - modsecurity-crs <no-dsa> (Minor issues; will be fixed in point release)
https://coreruleset.org/20220919/crs-version-3-3-3-and-3-2-2-covering-several-cves/
Depends on changes to be done in src:libmodsecurity3 / src:modsecurity-apache, cf.
https://bugs.debian.org/1020303