CVE-2026-50052: The Vinyl Cache Project Varnish Cache Pre Split

Low severity, CVSS 2.3. EPSS: 0.5% chance of exploitation in the next 30 days.

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.

Affected products

• The Vinyl Cache Project Varnish Cache Pre Split: from 7.6.0, up to and including 8.0.1; from 6.0.14, up to and including 6.0.17
• The Vinyl Cache Project Vinyl Cache: version 9.0.0 only
• Varnish Software Varnish Cache By Varnish Software: from 9.0.0, up to and including 9.0.2

Published 2026-06-03. Last modified 2026-07-22.