CVE-2026-54566 (GCVE-0-2026-54566)
Vulnerability from cvelistv5 – Published: 2026-10-14 19:08 – Updated: 2026-10-14 19:45
VLAI
EPSS
VEX
Title
Markdown Preview Enhanced: Remote Code Execution via VM Sandbox Escape in `.crossnote/config.js` and `.crossnote/parser.js`
Summary
Markdown Preview Enhanced is a Markdown preview extension for Visual Studio Code. Prior to 0.8.29, Markdown Preview Enhanced evaluates repository-controlled .crossnote/config.js and .crossnote/parser.js files with vm.runInNewContext, which does not provide a security boundary from the Node.js host realm. Opening a Markdown file in a malicious repository automatically loads these files, and prototype-chain traversal can reach the host Function constructor and process object, allowing operating-system commands to execute as the victim account without further interaction. Both configuration evaluation and parser-hook evaluation are affected, and the attack does not depend on module-scoped require being available. This issue is fixed in version 0.8.29.
Severity
SSVC
Exploitation: poc
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-14 19:44 UTC
CWE
- CWE-94 - Improper Control of Generation of Code ('Code Injection')
Assigner
References
7 references
| URL | Tags |
|---|---|
| https://github.com/shd101wyy/vscode-markdown-prev… | x_refsource_CONFIRM |
| https://github.com/shd101wyy/crossnote/pull/443 | x_refsource_MISC |
| https://github.com/shd101wyy/vscode-markdown-prev… | x_refsource_MISC |
| https://github.com/shd101wyy/crossnote/commit/e48… | x_refsource_MISC |
| https://github.com/shd101wyy/vscode-markdown-prev… | x_refsource_MISC |
| https://github.com/shd101wyy/crossnote/releases/t… | x_refsource_MISC |
| https://github.com/shd101wyy/vscode-markdown-prev… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| shd101wyy | vscode-markdown-preview-enhanced |
Affected:
< 0.8.29
|
guessed |
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],
"url": "https://github.com/shd101wyy/vscode-markdown-preview-enhanced/commit/0d4010988c6ae56a38c6dec4a7509cbd5a7dcb4c"
},
{
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"tags": [
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"discovery": "UNKNOWN"
},
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}
},
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"cveId": "CVE-2026-54566",
"datePublished": "2026-10-14T19:08:43.663Z",
"dateReserved": "2026-06-15T19:15:27.342Z",
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}
],
"id": "CVE-2026-54566",
"lastModified": "2026-10-14T20:17:47.403",
"metrics": {
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"Recovery": "NOT_DEFINED",
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"modifiedAttackComplexity": "NOT_DEFINED",
"modifiedAttackRequirements": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"modifiedPrivilegesRequired": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedVulnAvailabilityImpact": "NOT_DEFINED",
"modifiedVulnConfidentialityImpact": "NOT_DEFINED",
"modifiedVulnIntegrityImpact": "NOT_DEFINED",
"privilegesRequired": "NONE",
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Nomenclature
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
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