CVE-2026-34763
Rack: Rack::Directory info disclosure and DoS via unescaped regex interpolation
No known exploitation. EPSS puts it in the 23rd percentile. A vendor fix is available.
What to do
The vendor has published a fix. Version details are below where the sources state them.
What it is
From the CVE record
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.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
0.3% chance of exploitation activity in the next 30 days, which ranks it in the 23rd percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
7 events over 113 days, from the signal feeds we watch.
- Patch availablerecord updated
- OpenVAS check added
- Patch availablerecord updated
- Publishedweakness classified
Affected products
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Scored 5.3 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality LowSome restricted information is disclosed, but limited in scope
- Integrity NoneNo integrity impact
- Availability NoneNo availability impact
Weaknesses
Sources
References in the record
- github.com/rack/rack/security/advisories/GHSA-7mqq-6cf9-v2qp
- github.com/rack/rack&
- github.com/rack/rack/security/advisories/GHSA-7mqq-6cf9-v2qp&
And 4 more references. See all after sign-in
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