HTTP Request Smuggling Affecting org.apache.tomcat.embed:tomcat-embed-core package, versions [8.5.67,9.0.122)[10.1.0-M1,10.1.60)[11.0.0-M1,11.0.26)
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.
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Test your applications- Snyk IDSNYK-JAVA-ORGAPACHETOMCATEMBED-21715433
- published26 Oct 2026
- disclosed23 Sept 2026
- creditUnknown
Introduced: 23 Sep 2026
CVE-2026-77756 (opens in a new tab)How to fix?
Upgrade org.apache.tomcat.embed:tomcat-embed-core to version 9.0.122, 10.1.60, 11.0.26 or higher.
Overview
org.apache.tomcat.embed:tomcat-embed-core is a Core Tomcat implementation.
Affected versions of this package are vulnerable to HTTP Request Smuggling via the Http11Processor in the HTTP/1.x request-processing component. An attacker can cause one request from another user to fail by sending an HTTP/1.0 request with a Transfer-Encoding header when Tomcat is behind a reverse proxy that interprets the request differently.