Description
In JetBrains TeamCity before 2026.2,
2026.1.4,
2025.11.8 remote code execution via a whitelist bypass in the build messages protocol was possible
Published: 2026-10-15
Score: 8.1 High
EPSS: < 1% Very Low
KEV: No
Impact: Remote Code Execution
Action: Immediate Patch
AI Analysis

Impact

JetBrains TeamCity software prior to versions 2026.2, 2026.1.4, and 2025.11.8 contains a deserialization flaw (CWE‑502) that allows an attacker to bypass the whitelist in the build messages protocol and execute arbitrary code. The vulnerability permits the execution of malicious code without authentication or additional privileges and can compromise the entire machine hosting TeamCity.

Affected Systems

The affected products are JetBrains TeamCity servers running any of the following software versions: any build before 2026.2, specifically 2026.1.4 and 2025.11.8, as identified by the JetBrains CNA.

Risk and Exploitability

The CVSS score of 8.1 indicates a high severity risk. The EPSS score is less than 1 %, so the current probability of exploitation is very low, but the vulnerability is not listed in the CISAV catalog. Based on the description, it is inferred that the likely attack vector is remote, where an attacker can send crafted build messages to trigger code execution.

Generated by OpenCVE AI on October 16, 2026 at 21:30 UTC.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Upgrade JetBrains TeamCity to version 2026.2 or later, which incorporates a fix for the deserialization flaw.
  • Restrict or disable the use of the build messages protocol for untrusted build requests, ensuring that only trusted builders or sources can send such messages.
  • Apply network segmentation and firewall rules to limit inbound connections to the TeamCity API endpoint to trusted IP addresses only.

Generated by OpenCVE AI on October 16, 2026 at 21:30 UTC.

Tracking

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Advisories

No advisories yet.

History

Fri, 16 Oct 2026 21:45:00 +0000

Type Values Removed Values Added
Title Deserialization Vulnerability Allows Remote Code Execution in TeamCity

Fri, 16 Oct 2026 19:30:00 +0000

Type Values Removed Values Added
First Time appeared Jetbrains
Jetbrains teamcity
CPEs cpe:2.3:a:jetbrains:teamcity:*:*:*:*:*:*:*:*
Vendors & Products Jetbrains
Jetbrains teamcity

Thu, 15 Oct 2026 17:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Thu, 15 Oct 2026 15:45:00 +0000

Type Values Removed Values Added
Description In JetBrains TeamCity before 2026.2, 2026.1.4, 2025.11.8 remote code execution via a whitelist bypass in the build messages protocol was possible
Weaknesses CWE-502
References
Metrics cvssV3_1

{'score': 8.1, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H'}

Subscriptions

Jetbrains Teamcity
cve-icon MITRE

Status: PUBLISHED

Assigner: JetBrains

Published:

Updated: 2026-10-16T03:57:00.108Z

Reserved: 2026-10-15T15:20:41.498Z

Link: CVE-2026-111094

cve-icon Vulnrichment

Updated: 2026-10-15T16:07:06.928Z

cve-icon NVD

Status : Analyzed

Published: 2026-10-15T16:17:48.993

Modified: 2026-10-16T19:19:17.150

Link: CVE-2026-111094

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-10-24T02:15:17Z

Weaknesses
  • CWE-502

    Deserialization of Untrusted Data