| Name | CVE-2026-34786 |
| Description | 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. |
| Source | CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| ruby-rack (PTS) | bullseye | 2.1.4-3+deb11u2 | vulnerable |
| bullseye (security) | 2.1.4-3+deb11u5 | vulnerable | |
| bookworm | 2.2.20-0+deb12u1 | vulnerable | |
| bookworm (security) | 2.2.22-0+deb12u1 | vulnerable | |
| trixie | 3.1.18-1~deb13u1 | vulnerable | |
| trixie (security) | 3.1.20-0+deb13u1 | vulnerable | |
| forky | 3.1.18-1 | vulnerable | |
| sid | 3.2.5-2 | vulnerable |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| ruby-rack | source | experimental | 3.2.6-1 | |||
| ruby-rack | source | (unstable) | (unfixed) |
https://github.com/rack/rack/security/advisories/GHSA-q4qf-9j86-f5mh
Fixed by: https://github.com/rack/rack/commit/d6af0639e25ec6f3cc12bf64baa4b991be0cbfa1 (v3.2.6)
Fixed by: https://github.com/rack/rack/commit/84937c38065d0a7630828fdd526201c5241a9619 (v3.1.21)
Fixed by: https://github.com/rack/rack/commit/4207d22e58a41d57a2c6e1ed2602170504b000c7 (v2.2.23)