Vulnerability · Published Oct 9, 2026 · Assigned by GitHub_M
CVE-2026-107833OWASP Coraza WAF: Unbounded recursion in JSON response body processor causes CPU exhaustion
Medium 5.9
In plain English
A medium-severity security flaw in coraza from corazawaf. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 33% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
OWASP Coraza WAF is a golang modsecurity compatible web application firewall library. From 3.0.0 until 3.8.0, ProcessResponse in internal/bodyprocessors/json.go passes the ignoreJSONRecursionLimit value of -1 to readJSON, while the recursive guard only stops at zero. A network attacker who can cause an application protected by Coraza to return deeply nested JSON can make response-body processing perform quadratic work, consuming one CPU core for seconds per response within the default ResponseBodyLimit. Request JSON processing is not affected by this specific path because it uses the configured request recursion limit, and exploitation requires response-body inspection to be enabled. This issue is fixed in version 3.8.0.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/corazawaf/coraza | no fix listed | GO-2026-6690 |
| Go | github.com/corazawaf/coraza/v2 | no fix listed | GO-2026-6690 |
| Go | github.com/corazawaf/coraza/v3 | 3.8.0 | GO-2026-6690 |
| Go | github.com/corazawaf/coraza/v3 | 3.8.0 | GHSA-3c6w-j9xm-8h2h |
Affected products (as reported)
Weakness: CWE-674 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
References
- https://github.com/corazawaf/coraza/security/advisories/GHSA-3c6w-j9xm-8h2h x_refsource_CONFIRM
- https://github.com/corazawaf/coraza/commit/cae3c7407e7b84372c207033de03f15f89bf351a x_refsource_MISC
- https://github.com/corazawaf/coraza/releases/tag/v3.8.0 x_refsource_MISC