Cyber Resilience

CVE-2026-22813

CriticalPublic PoC

Published: 12 January 2026

Published
12 January 2026
Modified
21 January 2026
KEV Added
—
Patch
—
CVSS Score v4 9.4 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/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
EPSS Score 0.0091 55.5th percentile
Risk Priority 70 floored blend · peak EPSS

Summary

CVE-2026-22813 is a critical-severity Cross-site Scripting (CWE-79) vulnerability in Anoma Opencode. Its CVSS base score is 9.4 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique JavaScript (T1059.007); ranked in the top 44.5% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

This vulnerability is AI-related — categorised as AI Agent Protocols and Integrations; in the LLM/Generative AI Risks risk domain.

OWASP Top 10 for Web (2025)

A05:2025 Injection

EU & UK References

Vulnerability details

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…

more

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.

CWE(s)
CWE-79

AI Security AnalysisAI

AI Category
AI Agent Protocols and Integrations
Risk Domain
LLM/Generative AI Risks
OWASP Top 10 for LLMs 2025
None mapped
Classification Reason
Matched keywords: ai, llm

Related Threats

Threat-Actor AttributionAI

Gamaredon Group (G0047)
Introducing the 2026 Cloudflare Threat Report
MuddyWater (G0069)
Introducing the 2026 Cloudflare Threat Report
Kimsuky (G0094)
Introducing the 2026 Cloudflare Threat Report
Mustang Panda (G0129)
Introducing the 2026 Cloudflare Threat Report
Volt Typhoon (G1017)
Introducing the 2026 Cloudflare Threat Report

MITRE ATT&CK Enterprise TechniquesAI

T1059.007 JavaScript Execution
Adversaries may abuse various implementations of JavaScript for execution.
attack.mitre.org →
T1189 Drive-by Compromise Initial Access
Adversaries may gain access to a system through a user visiting a website over the normal course of browsing.
attack.mitre.org →
Why these techniques?

XSS via unsanitized LLM markdown output directly enables JavaScript execution (T1059.007) and drive-by compromise through rendered content (T1189).

Confidence: MEDIUM · MITRE ATT&CK Enterprise v19.0

Affected Assets

anoma
opencode
≤ 1.1.10

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

CA-8 Penetration Testing
addresses: CWE-79

Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.

SI-10 Information Input Validation
addresses: CWE-79

Validates web inputs to reject script-related content that could produce XSS.

SI-15 Information Output Filtering
addresses: CWE-79

Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.

References