CVE-2026-28369

The record

A flaw was found in Undertow. When Undertow receives an HTTP request where the first header line starts with one or more spaces, it incorrectly processes the request by stripping these leading spaces. This behavior, which violates HTTP standards, can be exploited by a remote attacker to perform request smuggling. Request smuggling allows an attacker to bypass security mechanisms, access restricted information, or manipulate web caches, potentially leading to unauthorized actions or data exposure.

Affected packages

Related vulnerabilities

• CVE-2026-112212 GitLab has remediated an issue in GitLab CE/EE affecting all versions from 18.3 before… CWE-444
• CVE-2026-111750 AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. CWE-444
• CVE-2026-88829 A flaw was found in BusyBox httpd's reverse proxy feature. CWE-444
• CVE-2026-94439 When an HTTP server handler sends a 2xx response to an HTTP/1 CONNECT request and returns… CWE-444
• CVE-2026-78660 Historically, we have been rather lax about malformed framing-related headers in our… CWE-444
• CVE-2026-56866 When http.Transport sends an HTTP/1 CONNECT request with a non-empty Request.Body, it… CWE-444
• CVE-2026-85078 Sanic is an opensource python web server/framework. CWE-444
• CVE-2026-81356 Inconsistent interpretation of http requests ('http request/response smuggling') in… CWE-444