CVE•Published 2026-04-02•Modified 2026-07-24•0 articles on news•4 live references•NVD data

CVE-2026-34763Rack · Rack

Vulnerability data via NVD (ingested)

CVSS v3.1

5.3

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

EPSS percentile

Exploit Prediction Scoring System · top 85% of all CVEs

Weaknesses (CWE)

CWE-625Permissive Regular Expression

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.

Timeline

Published 2026-04-02

Modified 2026-07-24

External references

NVD MITRE Exploit-DB VulnCheck

Search for exposed instances

Shodan + Censys queries derived from NVD's CPE data. The vuln tag catches assets Shodan has explicitly linked to this CVE; the product / banner fingerprints find exposed instances even when the vuln tag was never applied (which is common). Live host counts are a Premium feature.

Shodan · vuln tag

vuln:CVE-2026-34763

Hosts Shodan has explicitly fingerprinted as vulnerable.

Shodan · product

product:"Rack Rack"

All exposed Rack Rack instances — cross-reference with the CVE's affected-version range.

Shodan · banner/body mention

http.html:"Rack"

HTTP body or banner mentions "Rack" — catches deploys Shodan didn't identify as a product.

More intel sources (5)

Shodan report

vuln:CVE-2026-34763