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TI-2022-18921 Aliases CVE-2022-39955GHSA-x6xv-j46p-v597

Partial rule set bypass in OWASP ModSecurity Core Rule Set by submitting a specially crafted HTTP Content-Type header

Priority MEDIUM 51CWE-863Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · High
Fix status
Will not fix Red Hat: no fix planned

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-863.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01421 72nd percentileScored 2026-11-07
Fix Will not fix Red Hat: no fix planned

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
owasp-modsecurityModSecurity Core Rule Set3.0.x; 3.1.x; up to 3.2.1; up to 3.3.2—No fix listedCNA
  • ModSecurity Core Rule Set Vendorowasp-modsecurity Affected 3.0.x; 3.1.x; up to 3.2.1; up to 3.3.2 Fixed in — No fix listed CNA

CPE configurations NVD · 5

CPEVersionsRoleVendor
cpe:2.3:a:owasp:owasp_modsecurity_core_rule_set:*:*:*:*:*:*:*:*3.0.0 to before 3.2.2; 3.3.0 to before 3.3.3Vulnerableowasp-modsecurity
cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*35VulnerableFedoraproject
cpe:2.3:o:fedoraproject:fedora:36:*:*:*:*:*:*:*36VulnerableFedoraproject
cpe:2.3:o:fedoraproject:fedora:37:*:*:*:*:*:*:*37VulnerableFedoraproject
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*10.0VulnerableDebian
  • cpe:2.3:a:owasp:owasp_modsecurity_core_rule_set:*:*:*:*:*:*:*:* Versions 3.0.0 to before 3.2.2; 3.3.0 to before 3.3.3 Vulnerable ·owasp-modsecurity
  • cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:* Versions 35 Vulnerable ·Fedoraproject
  • cpe:2.3:o:fedoraproject:fedora:36:*:*:*:*:*:*:* Versions 36 Vulnerable ·Fedoraproject
  • cpe:2.3:o:fedoraproject:fedora:37:*:*:*:*:*:*:* Versions 37 Vulnerable ·Fedoraproject
  • cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* Versions 10.0 Vulnerable ·Debian

Remediation

No fixed version listed by the sources yet.

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Advisory ·

    OWASP ModSecurity Core Rule Set — FEDORA-2022-1fd73a5285

    4 records Highest priority Priority MEDIUM 4 MEDIUM

    Other records, highest priority first

    • TI-2022-18922 Incorrect authorization in owasp-modsecurity ModSecurity Core Rule SetPriority MEDIUM 50
    • TI-2022-18924 Incorrect authorization in owasp-modsecurity ModSecurity Core Rule SetPriority MEDIUM 41
    • TI-2022-18923 Response body bypass in OWASP ModSecurity Core Rule Set via a specialy crafted charset in the HTTP Accept headerPriority MEDIUM 41
    Show all 4 records → Advisory →
  • Advisory ·

    OWASP ModSecurity Core Rule Set — FEDORA-2022-90708b46e3

    4 records Highest priority Priority MEDIUM 4 MEDIUM

    Other records, highest priority first

    • TI-2022-18922 Incorrect authorization in owasp-modsecurity ModSecurity Core Rule SetPriority MEDIUM 50
    • TI-2022-18924 Incorrect authorization in owasp-modsecurity ModSecurity Core Rule SetPriority MEDIUM 41
    • TI-2022-18923 Response body bypass in OWASP ModSecurity Core Rule Set via a specialy crafted charset in the HTTP Accept headerPriority MEDIUM 41
    Show all 4 records → Advisory →
Show 1 more group
  • Advisory ·

    OWASP ModSecurity Core Rule Set — FEDORA-2022-85a85c84b3

    4 records Highest priority Priority MEDIUM 4 MEDIUM

    Other records, highest priority first

    • TI-2022-18922 Incorrect authorization in owasp-modsecurity ModSecurity Core Rule SetPriority MEDIUM 50
    • TI-2022-18924 Incorrect authorization in owasp-modsecurity ModSecurity Core Rule SetPriority MEDIUM 41
    • TI-2022-18923 Response body bypass in OWASP ModSecurity Core Rule Set via a specialy crafted charset in the HTTP Accept headerPriority MEDIUM 41
    Show all 4 records → Advisory →

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 7AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 8AffectedNo fix planned: Will not fix
Red Hat Enterprise Linux 9AffectedNo fix planned: Will not fix

Timeline

  1. 2026-10-02 Threatist record created from CVE-2022-39955
  2. 2026-10-03 Alias added: GHSA-x6xv-j46p-v597

References

Patch 1

Advisory 5

  • TI-2026-17577 OWASP CRS has multipart bypass using multiple content-type parts CVSS 3.1CRITICAL 9.3
  • TI-2022-18922 Incorrect authorization in owasp-modsecurity ModSecurity Core Rule Set CVSS 3.1CRITICAL 9.8
  • TI-2021-14182 OWASP ModSecurity Core Rule Set 3.1.x before 3.1.2, 3.2.x before 3.2.1, and 3.3.x before… CVSS 3.1CRITICAL 9.8
  • TI-2020-14375 Modsecurity owasp-modsecurity-crs 3.2.0 (Paranoia level at PL1) has a SQL injection… CVSS 3.1CRITICAL 9.8
  • TI-2022-18924 Incorrect authorization in owasp-modsecurity ModSecurity Core Rule Set CVSS 3.1HIGH 7.5
  • TI-2022-18923 Response body bypass in OWASP ModSecurity Core Rule Set via a specialy crafted charset in the HTTP Accept header CVSS 3.1HIGH 7.5
See all 8 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences