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CVE-2026-63077

JetBrains TeamCity

score 85Known exploited · added 2026-08-05Used in ransomwarePublic PoC ×6Nuclei template

Summary

JetBrains TeamCity Deserialization of Untrusted Data Vulnerability

JetBrains TeamCity contains a deserialization of untrusted data vulnerability that could allow unauthenticated remote code execution via the agent polling protocol.

Published 2026-08-05 · first seen here 2026-10-10

CISA required action (due 2026-08-08): 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.

Exploit availability

Public exploit code lowers the bar for attackers, so prioritise patching and hunting. These repositories are unverified. Fake PoCs that contain malware are common, so never run them outside an isolated lab.

Hunt & detect

Threat hunt brief, Sigma rule and Splunk / Sentinel / CrowdStrike queries are not available for this item yet.

References