CVE-2023-42793
Auth Bypass in Jetbrains Teamcity ≤ 2023.05.4
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HSummary
CVE-2023-42793 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; a public proof-of-concept is referenced.
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-2023-42793 is an authentication bypass vulnerability affecting JetBrains TeamCity servers prior to version 2023.05.4. The flaw, assigned CWE-288 and CWE-306, permits unauthenticated network access that leads directly to remote code execution on the TeamCity Server and carries a CVSS 3.1 base score of 9.8.
An attacker with network reachability can exploit the issue without credentials or user interaction to obtain full control of the server, including the ability to read, modify, or delete data and execute arbitrary code. The attack vector is reflected in the CVSS metrics AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
JetBrains published a post-mortem and an updated list of fixed issues recommending immediate upgrade to TeamCity 2023.05.4 or later; additional technical analysis and proof-of-concept material appear in Rapid7 and AttackerKB reporting. The associated EPSS score has remained consistently high, reaching a peak of 0.9749 with a current value of 0.9291.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2023-47222
Vulnerability Data
In JetBrains TeamCity before 2023.05.4 authentication bypass leading to RCE on TeamCity Server was possible
- CWE(s)
- KEV Date Added
- 04 October 2023
Related Threats
Threat-Actor AttributionAI
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 13 hardening rules · 4 OS baselines
V6.4.3V6.6.1V12.1.3V6.2.3
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Mandates additional authentication for access under defined conditions, ensuring critical or high-risk functions are not left without authentication.
Identity providers mandate authentication for functions that would otherwise lack it.
Requires authentication for non-organizational users, preventing access to critical functions without proper identification and authentication.
Requires established identification and authentication to unlock, mitigating missing authentication for continued system access.
Requiring identification and rationale for actions allowed without authentication ensures critical functions are not left unprotected by forcing review of authentication requirements.
Authorizing remote access reduces the ability to bypass authentication via unauthorized alternate remote channels.
Authorizing mobile device connections to organizational systems ensures authentication is performed for this critical access function.
Guarantees critical functions are protected by mandatory invocation of the access control mechanism.
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.
Requiring authentication on every channel and path directly eliminates alternate-path bypasses.
Enforcing authorizations and least privilege across all access vectors prevents unauthenticated alternate paths.
Protecting networks and environments from unauthorized logical access blocks bypass via undocumented channels.
Managing identities and credentials is a prerequisite for authentication but does not itself enforce it on critical functions.
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.
The control explicitly calls for authentication before any critical function is reached, eliminating the possibility of bypassing authentication for high-value operations.
Security testing can detect alternate-path bypasses but does not prevent them in production.
Access control policy directly addresses alternate authentication paths by requiring all channels to enforce authentication.
Authentication information management ensures credentials and mechanisms are consistently applied across all access paths.
Access rights provisioning and review prevent bypass via unmonitored or alternate channels.
Mandating authentication requirements for critical functions at the requirements-gathering stage ensures that essential operations are not left unprotected by missing login or verification mechanisms.
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 (3 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, CWE-306
- V-248585 OL 8 must require reauthentication when using the "sudo" command. prevents CWE-306
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 (4 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, CWE-306
- V-204424 The Red Hat Enterprise Linux operating system must not allow accounts configured with blank or null passwords. prevents CWE-288
RHEL 8 (2 rules)
- V-230492 RHEL 8 must not have the rsh-server package installed. prevents CWE-306
- V-237643 RHEL 8 must require re-authentication when using the "sudo" command. prevents CWE-306