Web Application Firewall Vulnerability in OWASP Coraza by Coraza WAF
CVE-2026-104774

5.8MEDIUM

Key Information:

Vendor

Corazawaf

Status
Coraza
Vendor
CVE Published:
12 October 2026

What is CVE-2026-104774?

The OWASP Coraza WAF, a web application firewall library, has a flaw in the t:jsDecode transformation from versions 3.0.0 to 3.8.0. This issue arises when a Javascript request contains octal escape sequences, which can lead to the backslash being incorrectly included in the octal buffer. Consequently, the ParseInt function fails, leading to the return of a null byte. Malicious attackers can exploit this flaw to bypass WAF rules that depend on t:jsDecode, permitting various attacks including cross-site scripting and SQL injection, ultimately compromising protected applications. The vulnerability has been addressed in version 3.8.0.

Affected Version(s)

coraza >= 3.0.0, < 3.8.0

References

https://github.com/corazawaf/coraza/security/advisories/G...
x_refsource_CONFIRM
https://github.com/corazawaf/coraza/commit/f9b7afdbcedce7...
x_refsource_MISC
https://github.com/corazawaf/coraza/releases/tag/v3.8.0
x_refsource_MISC

CVSS V3.1

Score:
5.8
Severity:
MEDIUM
Confidentiality:
None
Integrity:
Low
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Changed

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.