ZeroDay Findings
Sign inSign up

Findings

CVE-2026-63077

JetBrains TeamCity Deserialization of Untrusted Data Vulnerability

Published Jul 27, 2026 · corrected/updated Aug 5, 2026 · JetBrains TeamCity · evidence confidence very high

Overview On July 27, 2026, JetBrains published a security advisory for CVE-2026-63077 , a critical unsafe deserialization vulnerability affecting JetBrains TeamCity . An attacker who can reach a TeamCity server over HTTP or HTTPS can exploit the agent polling protocol without credentials and execute operating system commands with the privileges of the TeamCity server process. JetBrains reported no known active exploitation when it disclosed the vulnerability. However, on August 5, 2026, CISA added CVE-2026-63077 to its Known Exploited Vulnerabilities (KEV) catalog, confirming exploitation in t

Grounded briefings

Catalog interpretations for three audiences. Each brief cites ingested metadata and the original advisories below. They are not independent research and they do not invent exploit steps.

Executive

CVE-2026-63077 is a critical public vulnerability record for JetBrains TeamCity. CISA lists it as known exploited. Published remediation guidance: 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. This summary is a catalog interpretation of the ingested metadata and cites the original advisories below.

System administrator

Identify whether JetBrains TeamCity is in your estate, then compare installed versions with the affected ranges. Affected packages or ranges on record: jetbrains/teamcity; JetBrains TeamCity. Published remediation guidance: 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. Prefer the vendor or distribution advisory linked in Sources before changing production systems. This is a catalog interpretation, not a runbook.

Security analyst

Signals on file: CVSS 9.8, EPSS 89.6%. CISA lists it as known exploited. Weakness classes: CWE-502. Sources contributing to this record: cisa_kev, cve_org, epss, metasploit. Public exploit references, when present, are outbound links only and are not proof of active exploitation. This is a catalog interpretation of stored metadata.

Exploitation and remediation

  • Exploitation evidence

    Confirmed in CISA KEV since Aug 5, 2026. Listed in the CISA Known Exploited Vulnerabilities catalog.

  • Patch and remediation

    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. CISA due date Aug 8, 2026.

  • Safe detection guidance

    Compare installed versions with the affected ranges below and verify the advisory from the original publisher. This site stores metadata and outbound links only; it does not ship exploit code or proof-of-concept payloads.

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

  1. Jul 27, 2026 · Catalog

    Detected

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

  2. Aug 5, 2026 · CISA KEV

    Known exploited

    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

  3. Aug 5, 2026 · Catalog

    Updated

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

  4. Aug 8, 2026 · CISA KEV

    Remediation due

    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

Affected

  • cpe jetbrains/teamcityversion unspecified
  • vendor JetBrains TeamCityversion unspecified

Sources

  • CISA KEVConfirmed exploitationCVE-2026-63077

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

    cisa.gov
  • CVE.orgVulnerability recordCVE-2026-63077

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2026-63077

    30-day exploitation probability 89.6%

    first.org
  • Metasploit ModulesPublic exploit moduleexploit_multi/http/jetbrains_teamcity_rce_cve_2026_63077

    Public module reference (excellent). Module source is not copied into this catalog.

    rapid7.com
  • NIST NVDVulnerability recordCVE-2026-63077

    In JetBrains TeamCity before 2026.1.3, 2025.11.7 unauthenticated remote code execution was possible via the agent polling protocol

    nvd.nist.gov
  • Rapid7 Vulnerability DatabaseResearchCVE-2026-63077

    Overview On July 27, 2026, JetBrains published a security advisory for CVE-2026-63077 , a critical unsafe deserialization vulnerability affecting JetBrains TeamCity . An attacker who can reach a TeamCity server over HTTP or HTTPS can exploit the agent polling protocol without credentials and execute operating system commands with the privileges of the TeamCity server process. JetBrains reported no

    rapid7.com

References