Low severity · published Jun 3, 2026
CVE-2026-50052
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),…
2.3
CVSS
0.4%
EPSS
No
On KEV
Description
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.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 32% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
VC
Varnish Cache (pre split) · The Vinyl Cache Project
7.6.0 through 8.0.1; 6.0.14 through 6.0.17 · source: vendor
VC
Varnish Cache by Varnish Software · Varnish Software
9.0.0 through 9.0.2 · source: vendor
VC
Vinyl Cache · The Vinyl Cache Project
9.0.0 · source: vendor
Affected product
VC
Varnish Cache (pre split)
The Vinyl Cache Project