CVE-2026-36537
CVE-2026-36537 is a critical-severity vulnerability with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-290.
Key facts
- Severity: Critical (CVSS 3.x base score 9.8)
- EPSS exploit prediction: 1% (40th percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-36747
- Weakness: CWE-290
- Published:
- Last modified:
Description
ThingsBoard v4.3.0.1 is vulnerable to an authentication bypass during the OAuth authorization code exchange. The application improperly trusts user-supplied identity data within the user parameter of the /login/oauth2/code/ endpoint. By manipulating the email address in this JSON object, a remote attacker can bypass authentication and gain full access to any existing user account on the platform without possessing the target user's credentials. This results in a complete account takeover.
Frequently asked questions
- What is CVE-2026-36537?
- ThingsBoard v4.3.0.1 is vulnerable to an authentication bypass during the OAuth authorization code exchange. The application improperly trusts user-supplied identity data within the user parameter of the /login/oauth2/code/ endpoint. By manipulating the email address in this JSON object, a remote attacker can bypass authentication and gain full access to any existing user account on the platform without possessing the target user's credentials. This results in a complete account takeover.
- How severe is CVE-2026-36537?
- CVE-2026-36537 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2026-36537 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (40th percentile), an estimate of the probability of exploitation in the next 30 days.
- How do I fix CVE-2026-36537?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- Does CVE-2026-36537 have an EU (EUVD) identifier?
- Yes. CVE-2026-36537 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-36747.
- When was CVE-2026-36537 published?
- CVE-2026-36537 was published on 2026-06-15 and last updated on 2026-06-17.
References
Other CWE-290 vulnerabilities
- CVE-2026-48567 — Critical (CVSS 10.0): Authentication bypass by spoofing in Azure HorizonDB allows an unauthorized attacker to elevate privileges over a…
- CVE-2026-6213 — Critical (CVSS 10.0): A vulnerability in Remote Spark SparkView before build 1122 allows an attacker to bypasses the local connection check…
- CVE-2026-39858 — Critical (CVSS 10.0): Traefik is an HTTP reverse proxy and load balancer. Prior to versions 2.11.43, 3.6.14, and 3.7.0-rc.2, there is a high…
- CVE-2025-66570 — Critical (CVSS 10.0): cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.27.0, a vulnerability…
- CVE-2025-34063 — Critical (CVSS 10.0): A cryptographic authentication bypass vulnerability exists in OneLogin AD Connector prior to 6.1.5 due to the exposure…
- CVE-2023-22814 — Critical (CVSS 10.0): An authentication bypass issue via spoofing was discovered in the token-based authentication mechanism that could allow…