CVE-2026-34060 Ruby LSP has arbitrary code execution through branch setting
Attackers can execute arbitrary Ruby code by crafting a malicious workspace setting in a project opened with Ruby LSP.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-34060?
CVE-2026-34060 is a high-severity code injection vulnerability in Shopify.ruby-lsp, published on 31 Mar 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official 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.
Weakness: CWE-94
Which versions are affected by CVE-2026-34060?
2 open source packages ship an affected version, including ruby-lsp. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
ruby-lsp RubyGems | All versions | 0.26.9 |
ruby-lsp RubyGems | All versions | 0.26.9 |
Products include Shopify Ruby Lsp.
How do I fix CVE-2026-34060?
Upgrade ruby-lsp to 0.26.9 or later.
Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.
Is CVE-2026-34060 being exploited?
There is no known exploitation of CVE-2026-34060 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-34060, GHSA-c4r5-fxqw-vh93.