CVE-2026-34763
Rack has a root directory disclosure via unescaped regex interpolation in Rack::Directory
5.3
MEDIUM
CVSS 3.1
EPSS 0.04%
Description
Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Directory interpolates the configured root path directly into a regular expression when deriving the displayed directory path. If root contains regex metacharacters such as +, *, or ., the prefix stripping can fail and the generated directory listing may expose the full filesystem path in the HTML output. This issue has been patched in versions 2.2.23, 3.1.21, and 3.2.6.
How to fix CVE-2026-34763
To remediate CVE-2026-34763, upgrade the affected package to a fixed version below.
- —no fix listed
- —upgrade to 2.2.23 or later
Is CVE-2026-34763 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- from 0
- from 0, < 2.2.23
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N |