What is CVE-2026-34785?

CVE-2026-34785 is a high-severity vulnerability in Rack, classified under Partial String Comparison. CVSS score: 7.5/10. Published 2026-04-02.

How severe is CVE-2026-34785?

High severity. CVSS v3 base score is 7.5 out of 10.

Information disclosure in Rack

CVE-2026-34785

Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Static determines whether a request should be served as a static file using a simple string prefix check. When configured with URL prefixes suc…

EPSS: 0.000 (14.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

Affected products

Rack — versions < 2.2.23, >= 3.0.0.beta1, < 3.1.21, >= 3.2.0, < 3.2.6

Weakness classification (CWE)

CWE-187 — Partial String Comparison
CWE-200 — Information Disclosure

References

https://github.com/rack/rack/security/advisories/GHSA-h2jq-g4cq-5ppq (x_refsource_CONFIRM)

Frequently asked questions

What is CVE-2026-34785?: CVE-2026-34785 is a high-severity vulnerability in Rack, classified under Partial String Comparison. CVSS score: 7.5/10. Published 2026-04-02.
How severe is CVE-2026-34785?: High severity. CVSS v3 base score is 7.5 out of 10.