Home/CVE/Varnish Cache before 8.0.1 and Varnish Enterprise before 6.0.16r12, in certain unchecked req.url scenarios, mishandle UR
CVE

CVE-2026-34475

Varnish Cache before 8.0.1 and Varnish Enterprise before 6.0.16r12, in certain unchecked req.url scenarios, mishandle UR

Varnish Cache before 8.0.1 and Varnish Enterprise before 6.0.16r12, in certain unchecked req.url scenarios, mishandle URLs with a path of / for HTTP/1.1, potentially leading to cache poisoning or authentication bypass.

MEDIUM · CVSS 5.4 EPSS 0.00067
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-180Incorrect Behavior Order: Validate Before Canonicalize
▤

Affected Products & Versions

3
varnish-software varnish enterprise<= 6.0.15
varnish-software varnish enterpriseall versions
vinyl-cache vinyl cache< 8.0.1
▣

Scoring & Timeline

5.4
MEDIUM · CVSS v3.1 · cve@mitre.org
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD27 Mar 2026 · 08:16 PM
CVSS VectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N
SSVC triage · cisa-vulnrichment
Exploitation
none
Automatable
no
Technical impact
partial
SSVC asks the questions that actually drive patch urgency: is it being exploited, can attacks be automated, and how total is the impact.
🔗

References & Sources

1
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://vinyl-cache.org/security/VSV00018.htmlMitigationVendor Advisory
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