What is CVE-2026-34786?

CVE-2026-34786 is a medium-severity vulnerability in Rack, classified under CWE-180. CVSS score: 5.3/10. Published 2026-04-02.

How severe is CVE-2026-34786?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Vulnerability in Rack

CVE-2026-34786

Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Static#applicable_rules evaluates several header_rules types against the raw URL-encoded PATH_INFO, while the underlying file-serving path is d…

EPSS: 0.000 (13.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/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-180

References

https://github.com/rack/rack/security/advisories/GHSA-q4qf-9j86-f5mh (x_refsource_CONFIRM)

Frequently asked questions

What is CVE-2026-34786?: CVE-2026-34786 is a medium-severity vulnerability in Rack, classified under CWE-180. CVSS score: 5.3/10. Published 2026-04-02.
How severe is CVE-2026-34786?: Medium severity. CVSS v3 base score is 5.3 out of 10.