PT-2026-35591 · Rubygems · Yard

Published 2026-04-17 · Updated 2026-04-17

OSV

CVSS v4.0

6.9

Medium

Base vector

AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

Impact

A path traversal vulnerability was discovered in YARD <= 0.9.41 when using yard server to serve documentation. This bug would allow unsanitized HTTP requests to access arbitrary files on the machine of a yard server host under certain conditions.

The original patch in GHSA-xfhh-rx56-rxcr was incorrectly applied.

Patches

Please upgrade to YARD v0.9.42 immediately if you are relying on yard server to host documentation in any untrusted environments without WEBrick and rely on --docroot.

Workarounds

For users who cannot upgrade, it is possible to perform path sanitization of HTTP requests at your webserver level. WEBrick, for example, can perform such sanitization by default (which you can use via yard server -s webrick), as can certain rules in your webserver configuration.

Exploit

Fix

Path traversal

Weakness Enumeration

CWE-22

Related Identifiers

GHSA-3JFP-46X4-XGFJ

Affected Products

Yard

References · 6

• 🔥 https://github.com/rubysec/ruby-advisory-db/blob/master/gems/yard/CVE-2026-41493.yml · Exploit
• https://osv.dev/vulnerability/GHSA-3jfp-46x4-xgfj · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-41493 · Security Note
• https://github.com/lsegal/yard/security/advisories/GHSA-3jfp-46x4-xgfj · Note
• https://github.com/lsegal/yard/releases/tag/v0.9.42 · Note
• https://github.com/lsegal/yard · Note