CVE-2026-34475

critical

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, poten…

Vendor / product: Varnish-software — varnish enterprise

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.

CVSS

9.8

9.8 (CVSS v3.1)

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Severity source: NVD CVSS v3.1 (nvd@nist.gov)

Timeline (UTC)

Published: 2026-03-27 20:16

Modified: 2026-10-26 22:10

NVD status: Analyzed

Last synced 2 days ago

Verified against the source API 2026-10-27 07:07 UTC

Exploitation

Not listed in CISA KEV (as of last catalog sync)

Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).

Affected products

varnish-software / varnish_enterprise ≤6.0.15, 6.0.16

vinyl-cache / vinyl_cache <8.0.1

Weakness classification (CWE)

CWE-180

Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.

Mitigation & advisories

Vendor advisory: https://vinyl-cache.org/security/VSV00018.html

Patch / mitigation: https://vinyl-cache.org/security/VSV00018.html

References

https://vinyl-cache.org/security/VSV00018.html cve@mitre.org

Data sources

NVD CVE API 2.0 — fetched 2026-10-27 07:07 UTC · record ↗

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