CVE-2026-34060 json
Ruby LSP has arbitrary code execution through branch setting
published 2026-03-27 7 mo ago modified 2026-06-17 4 mo ago also GHSA-c4r5-fxqw-vh93 , EUVD-2026-17282
- cvss
- 9.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 42%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- rubygems ruby-lsp 0.26.9
- shopify ruby_lsp 0.10.2, 0.26.9
- ruby-ruby-lsp Debian 14 0.26.9-0.1
debian advisories DEBIAN-CVE-2026-34060
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- total
- Assessed
- 7 mo ago
Exploit prediction
0.50% chance of exploitation in the next 30 days, higher than 42% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 7.1 | CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N |
| CISA ADP | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| CNA | 4.0 | 7.1 | CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
| CNA | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| rubygems | ruby-lsp | <0.26.9 |
0.26.9 |
Affected products
- Shopify ruby-lsp
- Shopify Shopify.ruby-lsp
Classification
- Weakness
-
- CWE-94 Improper Control of Generation of Code
References
-
github.com
/Shopify/ruby-lsp/security/advisories/GHSA-c4r5-fxqw-vh93
web, mitigation, vendor-advisory
-
github.com
/Shopify/ruby-lsp/releases/tag/v0.26.9
web, release-notes
-
nvd.nist.gov
/vuln/detail/CVE-2026-34060
advisory
-
github.com
/Shopify/ruby-lsp
package
-
github.com
/rubysec/ruby-advisory-db/blob/master/gems/ruby-lsp/CVE-2026-34060.yml
web
Sources
- CVE List CVE-2026-34060
- GitHub Advisory GHSA-c4r5-fxqw-vh93
- NVD CVE-2026-34060
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.