CVE-2026-34060

CRITICAL

Ruby LSP has arbitrary code execution through branch setting

Title source: cna
STIX 2.1

Description

Ruby LSP is an implementation of the language server protocol for Ruby. Prior to Shopify.ruby-lsp version 0.10.2 and ruby-lsp version 0.26.9, the rubyLsp.branch VS Code workspace setting was interpolated without sanitization into a generated Gemfile, allowing arbitrary Ruby code execution when a user opens a project containing a malicious .vscode/settings.json. This issue has been patched in Shopify.ruby-lsp version 0.10.2 and ruby-lsp version 0.26.9.

References (2)

Scores

CVSS v3 9.8
EPSS 0.0003
EPSS Percentile 7.8%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact total

Details

CWE
CWE-94
Status published
Products (3)
rubygems/ruby-lsp 0 - 0.26.9RubyGems
Shopify/ruby-lsp < 0.26.9
Shopify/Shopify.ruby-lsp < 0.10.2
Published Mar 31, 2026
Tracked Since Mar 31, 2026