Cyber Resilience

CVE-2024-27198

Auth Bypass in Jetbrains Teamcity ≤ 2023.11.4

CISA KEVActive ExploitationEUVD ExploitedRansomware-linkedAuth Bypass
Published
04 March 2024
Modified
17 June 2026
KEV Added
07 March 2024
Patch / advisory
CVSS Score v3.1 9.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.99 100.0th percentile
Risk Priority 97 floored blend · peak EPSS

Summary

CVE-2024-27198 is a critical-severity Authentication Bypass Using an Alternate Path or Channel (CWE-288) vulnerability in Jetbrains Teamcity. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 0.0% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog.

The strongest mitigations our analysis identified map to AC-25 (Reference Monitor) and AC-3 (Access Enforcement) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2024-27198 is an authentication bypass vulnerability affecting JetBrains TeamCity versions prior to 2023.11.4. The flaw, tracked under CWE-288, permits unauthenticated attackers to perform administrative actions on the continuous integration server, carrying a CVSS 3.1 base score of 9.8 reflecting network-accessible exploitation with no required credentials or user interaction.

An attacker with network access to an unpatched TeamCity instance can directly invoke administrative functionality, resulting in full compromise of confidentiality, integrity, and availability of the build system and any connected resources.

JetBrains has addressed the issue in TeamCity 2023.11.4 and later releases, as documented on its security issues page. The vulnerability is also listed in CISA's Known Exploited Vulnerabilities catalog, indicating that federal agencies and other organizations should prioritize patching according to the agency's guidance.

Public reporting confirms active mass exploitation of the flaw, with threat actors creating rogue administrative accounts on exposed instances. The associated EPSS score reached a peak of 0.9725 and remains elevated at 0.9305.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

In JetBrains TeamCity before 2023.11.4 authentication bypass allowing to perform admin actions was possible

CWE(s)
KEV Date Added
07 March 2024

Related Threats

MITRE ATT&CK Enterprise Techniques

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1211 Exploitation for Stealth Stealth
Adversaries may exploit vulnerabilities to evade detection by hiding activity, suppressing logging, or operating within trusted or unmonitored components.
T1542.002 Component Firmware Stealth
Adversaries may modify component firmware to persist on systems.
T1556 Modify Authentication Process Defense Impairment
Adversaries may modify authentication mechanisms and processes to access user credentials or enable otherwise unwarranted access to accounts.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-42793Same product: Jetbrains Teamcityboth on KEV
CVE-2024-36470Same product: Jetbrains Teamcity
CVE-2024-23917Same product: Jetbrains Teamcity
CVE-2024-27199Same product: Jetbrains Teamcityboth on KEV
CVE-2026-63077Same product: Jetbrains Teamcityboth on KEV
CVE-2024-56349Same product: Jetbrains Teamcity
CVE-2026-59796Same product: Jetbrains Teamcity
CVE-2026-49378Same product: Jetbrains Teamcity
CVE-2026-49374Same product: Jetbrains Teamcity
CVE-2026-28195Same product: Jetbrains Teamcity

Affected Assets

jetbrains
teamcity
≤ 2023.11.4

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 7 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V6.4.3
  • V6.6.1
  • V12.1.3

Mitigating Controls (NIST 800-53 r5) AI

Requires a tamperproof, always-invoked reference monitor that structurally blocks bypass via any alternate path.

Enforces authorization checks on every logical access path, eliminating unauthenticated alternate channels.

Mandates unique identification and authentication for all organizational users, covering the primary authentication requirement.

Controls all external and key internal interfaces, reducing the chance of unauthenticated alternate channels.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-03 full match
prevents

Requiring authentication on every channel and path directly eliminates alternate-path bypasses.

PR.AA-05 mostly match
prevents

Enforcing authorizations and least privilege across all access vectors prevents unauthenticated alternate paths.

PR.IR-01 mostly match
prevents

Protecting networks and environments from unauthorized logical access blocks bypass via undocumented channels.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing can detect alternate-path bypasses but does not prevent them in production.

degrades

Secure authentication control directly mitigates bypass by requiring strong, consistent authentication on all paths.

prevents

Access control policy directly addresses alternate authentication paths by requiring all channels to enforce authentication.

degrades

Authentication information management ensures credentials and mechanisms are consistently applied across all access paths.

prevents

Access rights provisioning and review prevent bypass via unmonitored or alternate channels.

prevents

Privileged access rights control reduces risk of bypass through elevated or alternate paths.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 8 (2 rules)
  • V-248598 There must be no ".shosts" files on the OL 8 operating system. prevents CWE-288
  • V-248827 OL 8 must not have the rsh-server package installed. prevents CWE-288
Oracle Linux 9 (2 rules)
  • V-271757 OL 9 file systems must not contain shosts.equiv files. prevents CWE-288
  • V-271758 OL 9 file systems must not contain .shosts files. prevents CWE-288
RHEL 7 (3 rules)
  • V-204440 Red Hat Enterprise Linux operating systems version 7.2 or newer using Unified Extensible Firmware Interface (UEFI) must require authentication upon booting into single-user and maintenance modes. prevents CWE-288
  • V-204442 The Red Hat Enterprise Linux operating system must not have the rsh-server package installed. prevents CWE-288
  • V-204424 The Red Hat Enterprise Linux operating system must not allow accounts configured with blank or null passwords. prevents CWE-288

References