# CVE-2026-59795: JetBrains TeamCity stored XSS in agent registration

Source: https://junglewise.ai/threats/cve-2026-59795-jetbrains-teamcity-stored-xss-in-agent-registration  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-10. Updated: 2026-07-10  
License: CC BY 4.0 with a link back

CVE-2026-59795 · Severity: high · CVSS 8.1 · Published 2026-07-10

JetBrains TeamCity, a platform used by software teams to automate building and testing code, is vulnerable to a security flaw in its build agent registration process. An unauthenticated attacker can inject malicious scripts into the system, which could allow them to hijack administrator sessions or steal sensitive data when a legitimate user views the affected management pages. This could lead to unauthorized access to the software development pipeline and corporate intellectual property.

Technologies: [Jetbrains TeamCity](https://junglewise.ai/threats/technologies/teamcity). Vendors: [Jetbrains](https://junglewise.ai/threats/vendors/jetbrains).

## Quick answers

**Is CVE-2026-59795 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-59795 being exploited in the wild.

**How severe is CVE-2026-59795?** High severity, with a CVSS score of 8.1, published 10 July 2026.

**Which products and versions are affected?** Jetbrains TeamCity before 2026.1.2.

**Is there a fix for CVE-2026-59795?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-59795 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-59795?** Check whether you run Jetbrains TeamCity at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A stored cross-site scripting (XSS) vulnerability exists in JetBrains TeamCity before version 2026.1.2. The flaw is located in the agent registration component, which fails to properly neutralize user-supplied input (CWE-79). An unauthenticated remote attacker can exploit this by registering a malicious build agent with a crafted payload. When a TeamCity administrator or authorized user interacts with the agent management interface, the malicious script executes in their browser context. This can lead to session hijacking, unauthorized configuration changes, or data exfiltration. The issue is resolved in TeamCity version 2026.1.2.

## Affected products

- JetBrains TeamCity before 2026.1.2

## Timeline

- 2026-07-10: disclosed
- 2026-07-10: advisory

## References

- [https://www.jetbrains.com/privacy-security/issues-fixed/](https://www.jetbrains.com/privacy-security/issues-fixed/)

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