CVE-2025-26492: JetBrains TeamCity Information Disclosure

CVE-2025-26492 Overview

CVE-2025-26492 is a critical vulnerability in JetBrains TeamCity that stems from improper Kubernetes connection settings handling. This security flaw could allow attackers to expose sensitive resources within Kubernetes environments when TeamCity is configured to interact with Kubernetes clusters. The vulnerability affects JetBrains TeamCity versions prior to 2024.12.2.

Critical Impact

Improper Kubernetes connection settings in TeamCity could expose sensitive cluster resources, potentially compromising confidentiality and integrity of containerized workloads and secrets.

Affected Products

• JetBrains TeamCity versions prior to 2024.12.2
• TeamCity installations with Kubernetes integration enabled
• CI/CD pipelines utilizing TeamCity-Kubernetes connections

Discovery Timeline

• 2025-02-11 - CVE-2025-26492 published to NVD
• 2025-05-16 - Last updated in NVD database

Technical Details for CVE-2025-26492

Vulnerability Analysis

This vulnerability is classified under CWE-522 (Insufficiently Protected Credentials), indicating that the TeamCity application fails to adequately protect credential information when establishing connections to Kubernetes clusters. The flaw exists in how TeamCity handles and stores Kubernetes connection settings, potentially allowing unauthorized access to sensitive Kubernetes resources.

The vulnerability is exploitable over the network without requiring user interaction or authentication. Successful exploitation could result in exposure of sensitive cluster resources including secrets, configuration maps, service account tokens, and other critical Kubernetes objects. While the vulnerability does not directly impact availability, the potential for credential exposure and resource access makes this a significant security concern for organizations running CI/CD pipelines with Kubernetes integration.

Root Cause

The root cause of CVE-2025-26492 lies in the improper handling of Kubernetes connection settings within TeamCity's configuration management. The application does not adequately protect or validate Kubernetes connection parameters, which can lead to unintended exposure of sensitive cluster resources. This may include insufficient access controls on stored credentials, improper certificate validation, or misconfigured service account permissions that TeamCity uses to interact with Kubernetes APIs.

Attack Vector

The attack vector for this vulnerability is network-based, requiring no user interaction or prior authentication. An attacker with network access to the TeamCity server could potentially exploit the improper Kubernetes connection settings to:

1. Access Kubernetes secrets and configuration data that should be protected
2. Enumerate cluster resources and service accounts
3. Potentially modify cluster configurations if write permissions are exposed
4. Pivot to other resources within the Kubernetes environment

The vulnerability requires low attack complexity, making it accessible to attackers with basic knowledge of Kubernetes and CI/CD systems.

Detection Methods for CVE-2025-26492

Indicators of Compromise

• Unusual API calls to Kubernetes clusters originating from TeamCity server IP addresses
• Unexpected access patterns to Kubernetes secrets or configuration maps
• Anomalous authentication events in Kubernetes audit logs associated with TeamCity service accounts
• Unauthorized enumeration of Kubernetes resources from CI/CD infrastructure

Detection Strategies

• Review TeamCity logs for suspicious Kubernetes connection activity
• Monitor Kubernetes audit logs for unauthorized resource access from TeamCity service accounts
• Implement network monitoring to detect unusual traffic between TeamCity and Kubernetes API servers
• Deploy SentinelOne agents on TeamCity servers to detect exploitation attempts

Monitoring Recommendations

• Enable verbose logging for Kubernetes connections in TeamCity for forensic analysis
• Configure alerts for Kubernetes API access from unexpected sources or with unusual patterns
• Implement continuous monitoring of TeamCity configuration changes, especially those related to Kubernetes integrations
• Use SentinelOne Singularity Platform to monitor for behavioral anomalies on TeamCity infrastructure

How to Mitigate CVE-2025-26492

Immediate Actions Required

• Upgrade JetBrains TeamCity to version 2024.12.2 or later immediately
• Audit existing Kubernetes connection configurations in TeamCity for potential exposure
• Rotate any Kubernetes credentials or service account tokens that may have been exposed
• Review Kubernetes RBAC policies to ensure TeamCity service accounts have minimum required permissions

Patch Information

JetBrains has addressed this vulnerability in TeamCity version 2024.12.2. Organizations should upgrade to this version or later to remediate the vulnerability. For detailed information about the security fix and other resolved issues, refer to the JetBrains Security Issues Fixed page.

Workarounds

• Temporarily disable Kubernetes integrations in TeamCity until the patch can be applied
• Implement network segmentation to restrict direct access between TeamCity and Kubernetes API servers
• Apply strict RBAC policies to limit the scope of TeamCity service accounts in Kubernetes
• Use temporary, short-lived credentials for Kubernetes connections where possible

# Example: Restrict TeamCity service account permissions in Kubernetes
kubectl create rolebinding teamcity-restricted \
  --clusterrole=view \
  --serviceaccount=ci-cd:teamcity-sa \
  --namespace=build-namespace

# Audit current service account permissions
kubectl auth can-i --list --as=system:serviceaccount:ci-cd:teamcity-sa