Quick answers
- Is CVE-2026-36537 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-36537 being exploited in the wild.
- How severe is CVE-2026-36537?
- Informational severity, with a CVSS score of 9.8, published 15 June 2026.
- Which products and versions are affected?
- ThingsBoard v4.3.0.1.
- Is there a fix for CVE-2026-36537?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-36537 attacked?
- It is attacked over the network, in a network appliance.
- Am I affected by CVE-2026-36537?
- Check whether you run ThingsBoard at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
An authentication bypass exists in ThingsBoard v4.3.0.1 due to improper validation of user-supplied identity data during the OAuth 2.0 flow. Specifically, the `/login/oauth2/code/` endpoint improperly trusts the `user` parameter within the JSON request body. A remote, unauthenticated attacker can intercept an OAuth login request (such as 'Sign in with Apple') and inject a `user` field containing a victim's email address. The server processes this manipulated request and issues a JWT access token for the victim's account instead of the attacker's. This allows for full account takeover without knowledge of the target's credentials. The issue is addressed in versions 4.2.2.1 and 4.3.1.1.
Affected products
- ThingsBoard ThingsBoard v4.3.0.1
Timeline
- 2026-06-10: other: PoC activity recorded
- 2026-06-15: disclosed: CVE published to NVD
- 2026-06-15: advisory