Critical severity · published Mar 31, 2026
CVE-2026-34060
Ruby LSP has arbitrary code execution through branch setting
9.8
CVSS
0.5%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 41% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SH
Shopify.ruby-lsp · Shopify
< 0.10.2 · source: vendor
RU
ruby-lsp · Shopify
< 0.26.9 · source: vendor
RL
Ruby Lsp · Shopify
before 0.10.2; before 0.26.9 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-34060
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-34060
Release Notes
https://github.com/Shopify/ruby-lsp/releases/tag/v0.26.9
Mitigation
https://github.com/Shopify/ruby-lsp/security/advisories/GHSA-c4r5-fxqw-vh93
More from ruby-lsp
5.4
CVE-2026-48122
Workspace settings can override executable and Gemfile paths used by the Ruby LSP VS Code extension