Quick answers
- Is CVE-2026-100255 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-100255 being exploited in the wild.
- How severe is CVE-2026-100255?
- High severity, with a CVSS score of 8.1, published 30 September 2026.
- Which products and versions are affected?
- Jetbrains TeamCity before 2026.2, 2026.1.4, 2025.11.8.
- Is there a fix for CVE-2026-100255?
- 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-2026-100255 attacked?
- It is attacked over the network, in a web application.
- Am I affected by CVE-2026-100255?
- Check whether you run Jetbrains TeamCity 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
The vulnerability exists in the password reset functionality of TeamCity, allowing unauthorized administrator account takeover. The issue affects TeamCity versions before 2026.2, 2026.1.4, and 2025.11.8. An attacker could exploit this to gain administrative privileges without requiring prior authentication, potentially leveraging network access or a lower-privileged account to initiate the attack.
Affected products
- JetBrains TeamCity before 2026.2, 2026.1.4, 2025.11.8
Timeline
- 2026-09-30: disclosed