HTTP Request Smuggling Affecting io.undertow:undertow-core package, versions [0,]
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
Do your applications use this vulnerable package?
In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.
Test your applications- Snyk IDSNYK-JAVA-IOUNDERTOW-15968277
- published10 Apr 2026
- disclosed27 Mar 2026
- creditUnknown
Introduced: 27 Mar 2026
CVE-2026-28369 (opens in a new tab)How to fix?
There is no fixed version for io.undertow:undertow-core.
Overview
io.undertow:undertow-core is a Java web server based on non-blocking IO.
Affected versions of this package are vulnerable to HTTP Request Smuggling due to incorrect handling of white-spaces in HTTP request headers. An attacker can gain unauthorized access to restricted information or perform unauthorized actions by sending specially crafted HTTP requests with leading spaces in the first header line.