Owasp Modsecurity Core Rule Set
CVE-2022-39956
CRITICAL
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A01:2025 - Broken Access Control
ASVS 5.0
V8 - Authorization Authorization logic validation
MITRE ATT&CK
1 technique across 1 tactic: Privilege Escalation The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 9.8 (CRITICAL). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. |
| Exploit ScenarioDerived | A remote attacker could bypass authorization checks to access restricted resources by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability. |
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Alert meAnalysisAI
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. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Incorrect Authorization vulnerability could allow attackers to bypass authorization checks to access restricted resources.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Review and test authorization logic, implement consistent access control checks, use centralized authorization framework.
Affects your stack
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Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
This vulnerability is classified as Incorrect Authorization (CWE-863), which allows attackers to bypass authorization checks to access restricted resources. 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). Affected products include: Owasp Owasp Modsecurity Core Rule Set, Fedoraproject Fedora, Debian Debian Linux.
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Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
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).
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Authentication bypass attacks exploit flaws in the verification mechanisms that control access to systems and applications.
Affected Products (CPE)NVD
OWASP ModSecurity Core Rule Set 3.1.x before 3.1.2, 3.2.x before 3.2.1, and 3.3.x before 3.3.2 is affected by a Request
OWASP Core Rule Set (CRS) before 4.22.0 and 3.3.8 has a bug in rule 922110 that allows WAF bypass on multipart requests.
An issue was discovered in OWASP ModSecurity Core Rule Set (CRS) 3.0.2. Rated high severity (CVSS 7.5), this vulnerabili
A SQL injection bypass (aka PL1 bypass) exists in OWASP ModSecurity Core Rule Set (owasp-modsecurity-crs) through v3.1.0
The OWASP ModSecurity Core Rule Set (CRS) is affected by a partial rule set bypass by submitting a specially crafted HTT
An issue was discovered in OWASP ModSecurity Core Rule Set (CRS) through 3.1.0. Rated medium severity (CVSS 5.3), this v
An issue was discovered in OWASP ModSecurity Core Rule Set (CRS) through 3.1.0. Rated medium severity (CVSS 5.3), this v
An issue was discovered in OWASP ModSecurity Core Rule Set (CRS) through 3.1.0. Rated medium severity (CVSS 5.3), this v
An issue was discovered in OWASP ModSecurity Core Rule Set (CRS) through 3.1.0. Rated medium severity (CVSS 5.3), this v
The OWASP ModSecurity Core Rule Set (CRS) is affected by a response body bypass to sequentially exfiltrate small and und
The OWASP ModSecurity Core Rule Set (CRS) is affected by a response body bypass. Rated high severity (CVSS 7.5), this vu
An issue was discovered in OWASP ModSecurity Core Rule Set (CRS) through 3.1.0. Rated medium severity (CVSS 5.3), this v
NVD
CVE.org
EPSS
GitHub PoC
Exploit-DB