EUVD-2026-101585

Markdown Preview Enhanced is a Markdown preview extension for Visual Studio Code. Prior to 0.8.30, the webview message handler in src/preview-provider.ts accepts an attacker-controlled command value and attacker-controlled args, constructs a command in the crossnote namespace, and invokes...

CVE-2026-54701 Markdown Preview Enhanced: Stored XSS via Unsanitized `.crossnote/head.html` Injection in Webview

Markdown Preview Enhanced is a Markdown preview extension for Visual Studio Code. Prior to 0.8.30, Markdown Preview Enhanced reads repository-controlled .crossnote/head.html content and passes it through resolvePathsInHeader before inserting it into the head of the preview webview document withou...

CVE-2026-54701

The Markdown Preview Enhanced extension for Visual Studio Code is vulnerable to Stored XSS in versions prior to 0.8.30 . The extension improperly handles repository-controlled content from .crossnote/head.html by passing it through resolvePathsInHeader and inserting it into the webview head witho...

CVE-2026-54701 Markdown Preview Enhanced: Stored XSS via Unsanitized `.crossnote/head.html` Injection in Webview

Markdown Preview Enhanced is a Markdown preview extension for Visual Studio Code. Prior to 0.8.30, Markdown Preview Enhanced reads repository-controlled .crossnote/head.html content and passes it through resolvePathsInHeader before inserting it into the head of the preview webview document withou...

CVE-2026-54703

The Markdown Preview Enhanced extension for Visual Studio Code is vulnerable to an arbitrary file write in versions prior to 0.8.30 . The root cause is that the _crossnote.updateMarkdown command accepts an arbitrary URI and attacker-controlled content, passing them to vscode.workspace.fs.writeFil...

CVE-2026-54703 Markdown Preview Enhanced: Arbitrary File Write via updateMarkdown Command Without Path Validation

Markdown Preview Enhanced is a Markdown preview extension for Visual Studio Code. Prior to 0.8.30, the crossnote.updateMarkdown command in Markdown Preview Enhanced accepts an arbitrary URI and attacker-controlled content, then passes them to vscode.workspace.fs.writeFile without validating that...

CVE-2026-54703 Markdown Preview Enhanced: Arbitrary File Write via updateMarkdown Command Without Path Validation

Markdown Preview Enhanced is a Markdown preview extension for Visual Studio Code. Prior to 0.8.30, the crossnote.updateMarkdown command in Markdown Preview Enhanced accepts an arbitrary URI and attacker-controlled content, then passes them to vscode.workspace.fs.writeFile without validating that...

CVE-2026-54566 Markdown Preview Enhanced: Remote Code Execution via VM Sandbox Escape in `.crossnote/config.js` and `.crossnote/parser.js`

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 hos...

CVE-2026-54566 Markdown Preview Enhanced: Remote Code Execution via VM Sandbox Escape in `.crossnote/config.js` and `.crossnote/parser.js`

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 hos...

EUVD-2026-101582

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 hos...

CVE-2026-54566

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 hos...

CVE-2026-54525 Markdown Preview Enhanced: One Click RCE via Markdown Link Command Injection on Windows

Markdown Preview Enhanced is a Markdown preview extension for Visual Studio Code. Prior to 0.8.28, Markdown Preview Enhanced preview-link handling passes a decoded, Markdown-controlled link target to a Windows file-opening helper that invokes childprocess.exec with the start command. When a Windo...

CVE-2026-54525

The Markdown Preview Enhanced extension for Visual Studio Code is vulnerable to OS Command Injection prior to version 0.8.28 . The root cause is the improper neutralization of special elements in the preview-link handling logic, where a decoded, Markdown-controlled link target is passed to a Wind...

CVE-2026-91159 Discourse: Stored oEmbed HTML injection via allowed iframe

Discourse is an open-source discussion platform. Prior to 2026.9.0, 2026.8.1, 2026.7.3, and 2026.1.9, oEmbed processing treated an entire attacker-controlled HTML fragment as trusted when the fragment contained an iframe whose source matched the configured allowlist. A user with posting permissio...

CVE-2026-54566: Improper Control of Generation of Code

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 hos...

CVE-2026-54525: Improper Neutralization of Special Elements used in an OS Command

Markdown Preview Enhanced is a Markdown preview extension for Visual Studio Code. Prior to 0.8.28, Markdown Preview Enhanced preview-link handling passes a decoded, Markdown-controlled link target to a Windows file-opening helper that invokes childprocess.exec with the start command. When a Windo...

CVE-2026-91159: Improper Neutralization of Input During Web Page Generation

Discourse is an open-source discussion platform. Prior to 2026.9.0, 2026.8.1, 2026.7.3, and 2026.1.9, oEmbed processing treated an entire attacker-controlled HTML fragment as trusted when the fragment contained an iframe whose source matched the configured allowlist. A user with posting permissio...

PT-2026-114203

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 hos...

PT-2026-114204

Name of the Vulnerable Software and Affected Versions Markdown Preview Enhanced versions prior to 0.8.30 Description This extension for Visual Studio Code reads content from the .crossnote/head.html file within a repository and processes it through the resolvePathsInHeader function before inserti...

CVE-2026-54701: Improper Neutralization of Input During Web Page Generation

Markdown Preview Enhanced is a Markdown preview extension for Visual Studio Code. Prior to 0.8.30, Markdown Preview Enhanced reads repository-controlled .crossnote/head.html content and passes it through resolvePathsInHeader before inserting it into the head of the preview webview document withou...