PT-2026-45903 · Vinyl Cache+1 · Varnish Cache+2

Published 2026-06-03 · Updated 2026-06-03 · CVE-2026-50052

Mitre

CVSS v4.0

2.3

Low

Base vector

AV:N/AC:H/AT:P/PR:N/UI:P/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N/S:N/AU:N/R:A/V:D/RE:L/U:Green

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.

Fix

HTTP Request/Response Smuggling

Weakness Enumeration

CWE-444

Related Identifiers

CVE-2026-50052

Affected Products

Varnish Cache

Varnish Cache By Varnish

Vinyl Cache

References · 2

• https://nvd.nist.gov/vuln/detail/CVE-2026-50052 · Security Note
• https://vinyl-cache.org/security/VSV00019.html · Note