HTTP Response Splitting Affecting getkirby/cms package, versions <4.9.4>=5.0.0-alpha.1, <5.4.4
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Test your applications- Snyk IDSNYK-PHP-GETKIRBYCMS-17423220
- published23 Jun 2026
- disclosed18 Jun 2026
- creditUnknown
Introduced: 18 Jun 2026
NewCVE-2026-50188 (opens in a new tab)Common Vulnerabilities and Exposures (CVE) are common identifiers for publicly known security vulnerabilities
Common Weakness Enumeration (CWE) is a category system for software weaknesses
Common Weakness Enumeration (CWE) is a category system for software weaknesses
How to fix?
Upgrade getkirby/cms to version 4.9.4, 5.4.4 or higher.
Overview
Affected versions of this package are vulnerable to HTTP Response Splitting via the headers option in the Remote process. An attacker can inject or override HTTP headers in outgoing requests by including newline characters in user-controlled input that is forwarded to the header value. This is only exploitable if custom code, plugins, or integrations pass untrusted input into the headers option of outgoing HTTP requests.