FreeBSD VuXML: Documenting security issues in FreeBSD and the FreeBSD Ports Collection

varnish -- HTTP/2 Request Forgery Vulnerability

Affected packages
varnish7 < 7.2.1
varnish6 <= 6.6.2


VuXML ID 5b8d8dee-6088-11ed-8c5e-641c67a117d8
Discovery 2022-11-08
Entry 2022-11-09

Varnish Cache Project reports:

A request forgery attack can be performed on Varnish Cache servers that have the HTTP/2 protocol turned on. An attacker may introduce characters through the HTTP/2 pseudo-headers that are invalid in the context of an HTTP/1 request line, causing the Varnish server to produce invalid HTTP/1 requests to the backend. This may in turn be used to successfully exploit vulnerabilities in a server behind the Varnish server.