CVE-2026-22813

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.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/anomalyco/opencode/security/advisories/GHSA-c83v-7274-4vgp	Vendor Advisory Exploit
https://github.com/anomalyco/opencode/security/advisories/GHSA-c83v-7274-4vgp	Vendor Advisory Exploit

Configurations

Configuration 1 (hide)

cpe:2.3:a:anoma:opencode:*:*:*:*:*:-:*:*

History

No history.

Information

Published : 2026-01-12 23:15

Updated : 2026-01-21 15:15

NVD link : CVE-2026-22813

Mitre link : CVE-2026-22813

CVE.ORG link : CVE-2026-22813

JSON object : View

Products Affected

anoma

opencode

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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