Main Vulnerability Database Vulnerabilities #VU59052

#VU59052 Uncontrolled Recursion in ModSecurity - CVE-2021-42717

Published: December 19, 2021

Vulnerability identifier: #VU59052

Vulnerability risk: Medium

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

CVE-ID: CVE-2021-42717

CWE-ID: CWE-674

Exploitation vector: Remote access

Exploit availability: No public exploit available

Vulnerable software:
ModSecurity

Software vendor:
Trustwave

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to uncontrolled recursion when processing excessively nested JSON objects. A remote attacker can send a specially crafted HTTP request and consume all available worker processes and CPU resources.

Remediation

Install updates from vendor's website.

External links

https://www.trustwave.com/en-us/resources/blogs/spiderlabs-blog/modsecurity-dos-vulnerability-in-json-parsing-cve-2021-42717/