CVE-2026-107833 OWASP Coraza WAF: Unbounded recursion in JSON response body processor causes CPU exhaustion
An attacker can cause CPU exhaustion in OWASP Coraza WAF by sending deeply nested JSON responses, requiring response-body inspection to be enabled.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-107833?
CVE-2026-107833 is a medium-severity denial of service vulnerability in corazawaf coraza, published on 9 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
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.
Weakness: CWE-674
Which versions are affected by CVE-2026-107833?
5 open source packages ship an affected version, including github.com/corazawaf/coraza/v3, github.com/corazawaf/coraza and github.com/corazawaf/coraza/v2.
| Package | Affected | Fixed in |
|---|---|---|
github.com/corazawaf/coraza/v3 Go | From 3.0.0 | 3.8.0 |
github.com/corazawaf/coraza/v3 Go | From 3.0.0 | 3.8.0 |
github.com/corazawaf/coraza/v3 Go | From 3.0.0 | 3.8.0 |
github.com/corazawaf/coraza Go | All versions | None |
github.com/corazawaf/coraza/v2 Go | All versions | None |
How do I fix CVE-2026-107833?
Upgrade github.com/corazawaf/coraza/v3 to 3.8.0 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-107833 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-107833 exists.
Sources
Also known as GHSA-3c6w-j9xm-8h2h, GO-2026-6690.