In Vinyl Cache before 9.0.1 and Varnish Cache before 9.0.3, a deficiency in HTTP/2 request parsing can be exploited to launch a backend request desync attack (request smuggling), which in turn can be used for cache poisoning, authentication bypass, or possibly even information disclosure and manipulation. The attack vector only exists if HTTP/2 support is enabled by setting the feature parameter to contain +http2. HTTP/2 support is disabled by default.

In Vinyl Cache before 9.0.1 and Varnish Cache before 9.0.3, a deficiency in HTTP/2 request parsing can be exploited to launch a backend request desync attack (request smuggling), which in turn can be used for cache poisoning, authentication bypass, or possibly even information disclosure and manipulation. The attack vector only exists if HTTP/2 support is enabled by setting the feature parameter to contain +http2. HTTP/2 support is disabled by default.

libvinylapi3-9.0.1-1.1 on GA media

Affected: Ubuntu:14.04:LTS: varnish, Ubuntu:Pro:16.04:LTS: varnish, Ubuntu:Pro:18.04:LTS: varnish, Ubuntu:Pro:20.04:LTS: varnish, Ubuntu:Pro:22.04:LTS: varnish, Ubuntu:24.04:LTS: varnish, Ubuntu:25.10: varnish, Ubuntu:26.04:LTS: varnish

In Vinyl Cache before 9.0.1 and Varnish Cache before 9.0.3, a deficiency in HTTP/2 request parsing can be exploited to launch a backend request desync attack (request smuggling), which in turn can be used for cache poisoning, authentication bypass, or possibly even information disclosure and manipulation. The attack vector only exists if HTTP/2 support is enabled by setting the feature parameter to contain +http2. HTTP/2 support is disabled by default.

Ein Angreifer kann eine Schwachstelle in Varnish HTTP Cache ausnutzen, um Dateien zu manipulieren, um Informationen offenzulegen, und um Sicherheitsvorkehrungen zu umgehen.