All vulnerabilities
CVE-2026-107835GHSA-g4qm-m288-5cp9GO-2026-6694

OWASP Coraza WAF: Cookie Parser Confusion

corazawaf corazaGoLibraries & packages
Open in ThreatlineRecord JSON
CVSS
4.0Medium
ExploitationPublic exploit codeCISA's assessment says proof of concept code is public, assessed 9 Oct 2026. Not in the KEV catalogCISA via CVE List
Exploit odds (EPSS)0.30%Chance of exploitation activity in the next 30 days, higher than 21% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in3.8.1Fixed versionOSV
Published9 Oct 2026Updated 19 Oct 2026CVE List

What fixes it

  • 3.8.1github.com/corazawaf/coraza/v3, GoOSVgo get github.com/corazawaf/coraza/v3@v3.8.1

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

Description

OWASP Coraza WAF is a golang modsecurity compatible web application firewall library. Prior to 3.8.1, internal/cookies.ParseCookies in internal/cookies/cookies.go handles boundary ASCII control characters and control-only or empty cookie names differently from several backend cookie parsers. An unauthenticated attacker can craft a Cookie header so Coraza indexes or drops a cookie under a different name or value from the backend application, causing rules targeting REQUEST_COOKIES or REQUEST_COOKIES_NAMES to miss application-visible attacker data. Exploitation depends on the backend parser and affected rule scope, and interior control characters with inconsistent backend behavior are outside this advisory's remediation. This issue is fixed in version 3.8.1.

Text from CVE List

Affected versions 2

  • corazaaffected: < 3.8.1CVE List
  • github.com/corazawaf/coraza/v3, Gofrom first release, fixed in 3.8.1OSV

References 4