CVE-2022-39955
Published: 20 September 2022
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.
Priority
Status
Package | Release | Status |
---|---|---|
modsecurity-crs Launchpad, Ubuntu, Debian |
bionic |
Needs triage
|
focal |
Needs triage
|
|
jammy |
Needs triage
|
|
kinetic |
Ignored
(end of life, was needs-triage)
|
|
lunar |
Ignored
(end of life, was needs-triage)
|
|
mantic |
Needs triage
|
|
noble |
Needs triage
|
|
trusty |
Ignored
(end of standard support)
|
|
upstream |
Needs triage
|
|
xenial |
Needs triage
|
Severity score breakdown
Parameter | Value |
---|---|
Base score | 9.8 |
Attack vector | Network |
Attack complexity | Low |
Privileges required | None |
User interaction | None |
Scope | Unchanged |
Confidentiality | High |
Integrity impact | High |
Availability impact | High |
Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |