CVE-2021-42717

Description

ModSecurity 3.x through 3.0.5 mishandles excessively nested JSON objects. Crafted JSON objects with nesting tens-of-thousands deep could result in the web server being unable to service legitimate requests. Even a moderately large (e.g., 300KB) HTTP request can occupy one of the limited NGINX worker processes for minutes and consume almost all of the available CPU on the machine. Modsecurity 2 is similarly vulnerable: the affected versions include 2.8.0 through 2.9.4.

Weakness classification

• nvd@nist.gov: CWE-674

Primary references

• cve@mitre.org — Mailing List, Third Party Advisory
• cve@mitre.org — Third Party Advisory
• cve@mitre.org — Patch, Third Party Advisory
• cve@mitre.org — Exploit, Mitigation, Vendor Advisory
• af854a3a-2127-422b-91ae-364da2661108 — Mailing List, Third Party Advisory
• af854a3a-2127-422b-91ae-364da2661108 — Third Party Advisory
• af854a3a-2127-422b-91ae-364da2661108 — Patch, Third Party Advisory
• af854a3a-2127-422b-91ae-364da2661108 — Exploit, Mitigation, Vendor Advisory