CVEvulnerability

CVE-2021-42717

7.5 HIGH Published 2021-12-07 Modified 2026-06-17 Official page ↗
Status
Modified
Published
2021-12-07
Last modified
2026-06-17
Assigner
[email protected]
CVSS 3.1 ([email protected])
7.5 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS 2.0 ([email protected])
5.0 MEDIUM — AV:N/AC:L/Au:N/C:N/I:N/A:P
Weaknesses
CWE-674

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.

Affected configurations

• owasp modsecurity (>= 3.0.0 < 3.0.6) • trustwave modsecurity (>= 2.0.0 < 2.9.5) • f5 nginx modsecurity waf r24 • f5 nginx modsecurity waf r25 • debian debian linux 9.0 • debian debian linux 10.0 • debian debian linux 11.0 • oracle http server 12.2.1.3.0 • oracle http server 12.2.1.4.0 • oracle zfs storage appliance kit 8.8

Related

Weakness · CWE (1)

  • CWE-674 Uncontrolled Recursion weakness

References