Quick answers
- Is CVE-2026-100254 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-100254 being exploited in the wild.
- How severe is CVE-2026-100254?
- High severity, with a CVSS score of 8.8, published 30 September 2026.
- Which products and versions are affected?
- Jetbrains TeamCity before 2026.2, 2026.1.4, and 2025.11.8.
- Is there a fix for CVE-2026-100254?
- 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-2026-100254 attacked?
- It is attacked over the network, in a web application.
- Am I affected by CVE-2026-100254?
- 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
A CRLF injection vulnerability exists in TeamCity's Pipeline Git connection settings that allows authenticated users to inject shell metacharacters and execute arbitrary OS commands on Windows build agents. The vulnerability requires authentication and access to Git connection configuration but does not require additional user interaction. A successful exploit grants an attacker command execution with the privileges of the TeamCity agent process.
Affected products
- JetBrains TeamCity before 2026.2, 2026.1.4, and 2025.11.8
Timeline
- 2026-09-30: disclosed