cvedb.io
CVE-2026-34786
MEDIUM · CVSS 5.3
EPSS exploitation probability: 0%
Published 2026-04-02T17:16:25.030 · Last modified 2026-06-17T10:39:37.400

Summary

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 decoded before the file is served. As a result, a request for a URL-encoded variant of a static path can serve the same file without the headers that header_rules were intended to apply. In deployments that rely on Rack::Static to attach security-relevant response headers to static content, this can allow an attacker to bypass those headers by requesting an encoded form of the path. This issue has been patched in versions 2.2.23, 3.1.21, and 3.2.6.

Affected products

rack — rack

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.