#VU54495 Protection mechanism failure in OWASP ModSecurity Core Rule Set (CRS) - CVE-2021-35368

Vulnerability identifier: #VU54495

Vulnerability risk: Medium

CVSSv4.0: 1.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-35368

CWE-ID: CWE-693

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
OWASP ModSecurity Core Rule Set (CRS)
Server applications / Other server solutions

Vendor: OWASP

Description

The vulnerability allows a remote attacker to bypass implemented security restrictions.

The vulnerability exists due to insufficient implementation of security measures within the default CRS ruleset. An attacker can bypass implemented security restrictions and exploit vulnerabilities in the CMS that is protected with ModSecurity with the OWASP ModSecurity Core Rule Set (CRS).

Mitigation
Install updates from vendor's website.

Vulnerable software versions

OWASP ModSecurity Core Rule Set (CRS): 3.0.0 - 3.0.2, 3.1.0 - 3.1.1, 3.2.0, 3.3.0

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External links
https://coreruleset.org/20210630/cve-2021-35368-crs-request-body-bypass/

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.