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.
References
Configurations
No configuration.
History
02 Apr 2026, 17:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-04-02 17:16
Updated : 2026-04-03 16:10
NVD link : CVE-2026-34786
Mitre link : CVE-2026-34786
CVE.ORG link : CVE-2026-34786
JSON object : View
Products Affected
No product.
CWE
CWE-180
Incorrect Behavior Order: Validate Before Canonicalize
