Is CVE-2026-107835 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-107835 being exploited in the wild.

How severe is CVE-2026-107835?

Medium severity, with a CVSS score of 4, published 9 October 2026.

Which products and versions are affected?

github.com/corazawaf/coraza (Go) SEMVER:introduced=0; github.com/corazawaf/coraza/v2 (Go) SEMVER:introduced=0; github.com/corazawaf/coraza/v3 (Go) SEMVER:introduced=0,fixed=3.8.1; OWASP Coraza WAF prior to 3.8.1.

Is there a fix for CVE-2026-107835?

Yes. github.com/corazawaf/coraza/v3 (Go): upgrade to 3.8.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-107835 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-107835?

Check whether you run github.com/corazawaf/coraza (Go), github.com/corazawaf/coraza/v2 (Go), github.com/corazawaf/coraza/v3 (Go) or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-107835: OWASP Coraza WAF cookie parsing bypass

CVE-2026-107835 · Severity: medium · CVSS 4 · Published 2026-10-09

OWASP Coraza is a web application firewall library that inspects incoming web traffic to block attacks. An attacker can craft malicious cookie headers with special control characters that Coraza parses differently from the backend web application, causing the firewall's security rules to miss the attacker's data and fail to block malicious requests.

Technologies: github.com/corazawaf/coraza (Go), github.com/corazawaf/coraza/v2 (Go), github.com/corazawaf/coraza/v3 (Go), OWASP Coraza WAF. Vendors: Go, OWASP.

Quick answers

Is CVE-2026-107835 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-107835 being exploited in the wild.
How severe is CVE-2026-107835?: Medium severity, with a CVSS score of 4, published 9 October 2026.
Which products and versions are affected?: github.com/corazawaf/coraza (Go) SEMVER:introduced=0; github.com/corazawaf/coraza/v2 (Go) SEMVER:introduced=0; github.com/corazawaf/coraza/v3 (Go) SEMVER:introduced=0,fixed=3.8.1; OWASP Coraza WAF prior to 3.8.1.
Is there a fix for CVE-2026-107835?: Yes. github.com/corazawaf/coraza/v3 (Go): upgrade to 3.8.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-107835 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-107835?: Check whether you run github.com/corazawaf/coraza (Go), github.com/corazawaf/coraza/v2 (Go), github.com/corazawaf/coraza/v3 (Go) or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

github.com/corazawaf/coraza/v3 (Go): upgrade to 3.8.1 or later
```
go get github.com/corazawaf/coraza/v3@v3.8.1
```

Technical details

The vulnerability exists in internal/cookies.ParseCookies in internal/cookies/cookies.go, which does not properly handle ASCII control characters (octets 0-31 and 127) adjacent to the cookie name/value delimiter. An attacker can craft a Cookie header where control characters cause Coraza to index or drop a cookie under a different name from the backend parser, allowing REQUEST_COOKIES and REQUEST_COOKIES_NAMES rules to miss application-visible data. The fix properly trims control characters from cookie name and value boundaries to align with RFC 6265 and common backend implementations.

Affected products

OWASP Coraza WAF prior to 3.8.1

Identifiers

CVE-2026-107835
GHSA-g4qm-m288-5cp9
GO-2026-6694

Timeline

2026-10-09: disclosed
2026-10-09: patched

References

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