CISA Flags TeamCity CVE-2026-63077 RCE Flaw Under Active Exploitation in the Wild
Overview
The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has issued a warning about a serious security flaw in JetBrains TeamCity, specifically affecting on-premise versions. The vulnerability, identified as CVE-2026-63077, has a high severity score of 9.8 and involves deserialization of untrusted data. This flaw allows unauthenticated attackers to potentially gain access to a TeamCity server, making it a significant risk for organizations using this software. As the vulnerability is currently being exploited in the wild, it is crucial for users to take immediate action to protect their systems. The timely patching of affected versions is paramount to mitigate this risk and ensure the security of sensitive data and operations.
Key Takeaways
- Active Exploitation: This vulnerability is being actively exploited by attackers. Immediate action is recommended.
- Affected Systems: JetBrains TeamCity (on-premise versions)
- Action Required: Users are advised to apply the latest patches from JetBrains to address CVE-2026-63077.
- Timeline: Newly disclosed
Original Article Summary
A newly patched security flaw impacting on-premise versions of JetBrains TeamCity has come under active exploitation in the wild, according to the U.S. Cybersecurity and Infrastructure Security Agency (CISA). The vulnerability in question is CVE-2026-63077 (CVSS score: 9.8), a case of deserialization of untrusted data that could allow an unauthenticated attacker with access to a TeamCity server
Impact
JetBrains TeamCity (on-premise versions)
Exploitation Status
This vulnerability is confirmed to be actively exploited by attackers in real-world attacks. Organizations should prioritize patching or implementing workarounds immediately.
Timeline
Newly disclosed
Remediation
Users are advised to apply the latest patches from JetBrains to address CVE-2026-63077. Specific patch details were not provided, but updating to the latest version is recommended.
Additional Information
This threat intelligence is aggregated from trusted cybersecurity sources. For the most up-to-date information, technical details, and official vendor guidance, please refer to the original article linked below.
Related Topics: This incident relates to CVE, Vulnerability, RCE.
Multiple Sources: This threat is being reported by 2 different security sources, indicating significant concern within the cybersecurity community.