Rack: Rack::Static header_rules bypass via URL-encoded paths (rack rack)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.20 % · percentile 10 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- GitHub_M
- NVD status
- Analyzed
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.
Weaknesses (CWE)
- CWE-180 — Incorrect Behavior Order: Validate Before Canonicalize
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | MEDIUM 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N | GitHub_M |
| CVSS 3.1 | MEDIUM 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N | NVD · security-advisories@github.com (Secondary) |
Advisories
- GHSA-q4qf-9j86-f5mh — Rack:: Static header_rules bypass via URL-encoded paths
European references
- ENISA EUVD · EUVD-2026-18384
- GCVE · GCVE-0-2026-34786
CERT-FR advisories
- CERTFR-2026-AVI-1352 — Multiples vulnérabilités dans Oracle PeopleSoft · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:a:rack:rack:*:*:*:*:*:ruby:*:*< 2.2.23cpe:2.3:a:rack:rack:*:*:*:*:*:ruby:*:*≥ 3.0.0 < 3.1.21cpe:2.3:a:rack:rack:*:*:*:*:*:ruby:*:*≥ 3.2.0 < 3.2.6
Affected products
| Product | Versions |
|---|---|
| rack · rack | affected < 2.2.23 ; affected >= 3.0.0.beta1, < 3.1.21 ; affected >= 3.2.0, < 3.2.6 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |