VDB
BIT-modsecurity-2021-42717
BIT-modsecurity-2021-42717
PUBLISHED
CVSS 7.5 HIGH
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.
Risk Scores
CVSS v3.1
7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Bitnami | modsecurity | 2.0.0, 2.0.0, 2.0.0 |
Timeline
- Mar 6, 2024 CVE Published
- Jul 4, 2025 CVE Updated
- Apr 30, 2026 Distribution Patch
References
- https://lists.debian.org/debian-lts-announce/2022/05/msg00042.html url
- https://www.debian.org/security/2021/dsa-5023 url
- https://www.oracle.com/security-alerts/cpuapr2022.html url
- https://www.trustwave.com/en-us/resources/blogs/spiderlabs-blog/modsecurity-dos-vulnerability-in-json-parsing-cve-2021-42717/ url
- https://nvd.nist.gov/vuln/detail/CVE-2021-42717 url