CRITICAL Actively exploited Used in ransomware CWE-502
CVE-2026-63077
JetBrains TeamCity Deserialization of Untrusted Data Vulnerability
JetBrains·TeamCity
9.8/ 10
CVSS 3.1
Critical severity
95%
EPSS exploit odds
Chance of exploitation in the next 30 days
Higher than 99.9% of all CVEs
Listed
CISA KEV catalog
- Added
- Aug 5, 2026
- Fix due
- Aug 8, 2026
- Ransomware
- Known use
Timeline
- Published
- Jul 27, 2026
- Updated
- Sep 23, 2026
- First covered
- Aug 6, 2026
- Latest story
- 3 months ago
Summary
In JetBrains TeamCity before 2026.1.3, 2025.11.7 unauthenticated remote code execution was possible via the agent polling protocol
Attack profile
Attack vectorNetwork
ComplexityLow
PrivilegesNone
User interactionNone
ScopeUnchanged
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HCISA required action
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
Affected products
- JetBrains TeamCitybefore 2026.1.3, 2025.11.7