Vulnerability · Published Jan 12, 2026 · Assigned by GitHub_M
CVE-2026-22813Malicious website can execute commands on the local system through XSS in the OpenCode web UI
Critical 9.4
In plain English
A critical-severity cross-site scripting in opencode from anomalyco. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.9% (higher than 60% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
OpenCode is an open source AI coding agent. The markdown renderer used for LLM responses will insert arbitrary HTML into the DOM. There is no sanitization with DOMPurify or even a CSP on the web interface to prevent JavaScript execution via HTML injection. This means controlling the LLM response for a chat session gets JavaScript execution on the http://localhost:4096 origin. This vulnerability is fixed in 1.1.10.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | opencode-ai | 1.1.10 | GHSA-c83v-7274-4vgp |
Affected products (as reported)
Weakness: CWE-79 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
References
- https://github.com/anomalyco/opencode/security/advisories/GHSA-c83v-7274-4vgp x_refsource_CONFIRM