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.

Severity (CVSS 3.1)5.9Medium
Exploit odds (30 days)0.4%top 66.9% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

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

EcosystemPackageFixed inAdvisory
Gogithub.com/corazawaf/corazano fix listedGO-2026-6690
Gogithub.com/corazawaf/coraza/v2no fix listedGO-2026-6690
Gogithub.com/corazawaf/coraza/v33.8.0GO-2026-6690
Gogithub.com/corazawaf/coraza/v33.8.0GHSA-3c6w-j9xm-8h2h

Affected products (as reported)

VendorProductVersions
corazawaf coraza >= 3.0.0, < 3.8.0

Weakness: CWE-674 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

References