# Urgent Security Alert: Critical Flaw in JetBrains TeamCity Exposes Systems to Remote Attacks

*Published July 31, 2026*
*Source: [https://www.bleepingcomputer.com/news/security/jetbrains-warns-of-critical-teamcity-remote-code-execution-flaw/](https://www.bleepingcomputer.com/news/security/jetbrains-warns-of-critical-teamcity-remote-code-execution-flaw/)*

## Executive Summary

JetBrains has identified a critical vulnerability in its TeamCity platform that could allow remote code execution in on-premises installations. Organizations must update their systems immediately to prevent potential security breaches.

## Article

JetBrains has issued an important warning about a critical vulnerability discovered in TeamCity, its widely used continuous integration and deployment platform. This flaw, identified as an authentication bypass, could allow attackers to execute remote code on affected systems if left unpatched. The vulnerability affects TeamCity's on-premises installations, making it crucial for organizations using this setup to act swiftly. Remote code execution flaws are particularly dangerous because they can enable attackers to take full control of a vulnerable system, potentially leading to data breaches or further network compromise. JetBrains has released a patch to address this issue and strongly advises all users to update their installations immediately. Security teams should prioritize this update to mitigate potential risks. Organizations relying on TeamCity are encouraged to review their current security measures, ensuring that systems are not only updated but also monitored for any signs of compromise. As part of a broader security strategy, teams should regularly test their systems using breach and attack simulation tools. According to a recent whitepaper by Picus, these tools help evaluate the effectiveness of security information and event management (SIEM) and endpoint detection and response (EDR) systems. Identifying gaps in these defenses can prevent threats from slipping through undetected, a common issue highlighted by statistics showing that only 14% of successful attacks are alerted upon. In conclusion, addressing this TeamCity vulnerability should be a top priority for affected organizations. Additionally, ongoing evaluation and improvement of security measures can help ensure a robust defense against evolving threats.