Vulnerability Intelligence Report
CVE-2021-42717
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.
No Active Exploit Signals
CVSS Base Score
7.5
HIGH
EPSS Probability:3.21%
Executive Threat Verdict
Evaluating...
Evaluating Threat Landscape...
Assessing known weaponization, exploitation telemetry, and federal advisories.
Attack Surface
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Authentication
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Weaponization
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SSVC Action
—
Affected Products & Versions
| Vendor | Product | Affected Versions |
|---|---|---|
| owasp | modsecurity | all |
| trustwave | modsecurity | all |
| f5 | nginx_modsecurity_waf | r24, r25 |
| debian | debian_linux | 9.0, 10.0, 11.0 |
| oracle | http_server | 12.2.1.3.0, 12.2.1.4.0 |
| oracle | zfs_storage_appliance_kit | 8.8 |
References & Technical Advisories
No reference links found.
Threat Intelligence Signals
EPSS Score
3.206%
GitHub Advisory
Identity & Timeline
| Status | PUBLISHED |
| Assigning Authority | MITRE Corporation · N/A · USA |
| Reserved | 2021-10-19T00:00:00 |
| Published | 2021-12-07T21:08:28 |
| Last Updated | 2024-08-04T03:38:49 |
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