Angular Language ServiceFramework / library · Angular
CVE-2026-50178
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedThe Angular Language Service VS Code Extension provides a rich editing experience for Angular templates. the client-side Angular Language Service VS Code extension configures the tooltip Markdown renderer with the isTrusted: true option (located in client/src/client.ts). This setting instructs VS Code to trust all rendered content it receives, which enables active elements such as command: URIs. However, the background Angular Language Server process fails to escape or sanitize brackets, raw links, and control characters from JSDoc strings before forwarding the hover Markdown content (located in server/src/handlers/hover.ts and server/src/text_render.ts). An attacker can leverage this behavior by crafting a project TypeScript or JavaScript file (or a third-party npm package dependency) containing a malicious JSDoc tooltip with an embedded active command link. When a developer hovers over the target symbol to render the tooltip and clicks the malicious link, the IDE executes the command sequence directly on the developer's host machine. Prior to 21.2.4, This vulnerability is fixed in 21.2.4.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceThe Angular Language Service VS Code Extension renders JSDoc tooltips with isTrusted:true, which allows command: URIs to execute. The server-side fails to sanitize JSDoc content before sending it to the client, allowing attackers to embed malicious command links in JSDoc comments. When developers hover and click these links, commands execute locally on their machines.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data
Angular Language ServiceFramework / library
< 21.2.4CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Check if Angular Language Service extension is installed in VS CodeOpen VS Code and go to Extensions view (Ctrl+Shift+X or Cmd+Shift+X), then search for 'Angular Language Service' in the installed extensions listAffected if The extension appears in the installed list
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Identify the installed version numberIn the Extensions view, click on the Angular Language Service extension to open its details panel; the version number is displayed in the extension informationAffected if Version number is visible and is less than 21.2.4 (e.g., 21.2.3, 21.2.0, etc.)
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Verify VS Code is configured to display hover tooltipsEnsure that hovering over Angular component symbols in .ts files triggers the Language Service tooltip feature; the vulnerability only applies when tooltips are renderedAffected if Hover tooltips are functional and display JSDoc content from source code
You are affected if the Angular Language Service VS Code extension is installed with a version lower than 21.2.4 and you use hover tooltips that display JSDoc content from your or third-party TypeScript files.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped21.2.4
Update the Angular Language Service VS Code extension to version 21.2.4 or later to receive the server-side sanitization fix.
21.2.4
- Open VS Code
- Navigate to the Extensions view (Ctrl+Shift+X or Cmd+Shift+X on Mac)
- Search for 'Angular Language Service' in the Extensions marketplace
- Locate the Angular Language Service extension in the results
- Click the 'Update' button if an update is available, or manually update to version 21.2.4
- Restart VS Code after the update completes to ensure the new version is loaded
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Angular Language Service
Scoped from the published advisory
- Consultation1.0 h
- Implementation1.0 h
- Testing1.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,200.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-50178 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-50178 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
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