CVE-2022-39955

Publication date 20 September 2022

Last updated 11 July 2025


Ubuntu priority

Cvss 3 Severity Score

7.3 · High

Score breakdown

Description

The OWASP ModSecurity Core Rule Set (CRS) is affected by a partial rule set bypass by submitting a specially crafted HTTP Content-Type header field that indicates multiple character encoding schemes. A vulnerable back-end can potentially be exploited by declaring multiple Content-Type "charset" names and therefore bypassing the configurable CRS Content-Type header "charset" allow list. An encoded payload can bypass CRS detection this way and may then be decoded by the backend. 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 to upgrade to 3.2.2 and 3.3.3 respectively.

Status

Package Ubuntu Release Status
modsecurity-crs 26.04 LTS resolute
Needs evaluation
25.10 questing Ignored end of life, was needs-triage
25.04 plucky Ignored end of life, was needs-triage
24.10 oracular Ignored end of life, was needs-triage
24.04 LTS noble
Needs evaluation
23.10 mantic Ignored end of life, was needs-triage
23.04 lunar Ignored end of life, was needs-triage
22.10 kinetic Ignored end of life, was needs-triage
22.04 LTS jammy
Needs evaluation
20.04 LTS focal
Needs evaluation
18.04 LTS bionic
Needs evaluation
16.04 LTS xenial
Needs evaluation
14.04 LTS trusty Ignored end of standard support

Severity score breakdown

CVSS version: CVSS v3.0

Base score 7.3 · High

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


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