Vulnerability report

Exploited in the wild Confirmed confidence In CISA KEV

CVE-2023-42793

TeamCity Authentication Bypass

JetBrains / TeamCity · affected before 2023.05.4

Watch CVE-2023-42793 Browse KEV feed
Severity
CVSS 9.8 · Critical
Confidence
Confirmed
Exploit status
Exploited in the wild
EPSS
100.0%
First observed
—
Last observed
—

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2023-42793 is an unauthenticated vulnerability affecting JetBrains TeamCity. In JetBrains TeamCity before 2023.05.4 authentication bypass leading to RCE on TeamCity Server was possible

Is it exploited?

Yes. Previdian tracks this CVE as a known exploited vulnerability. Confidence is confirmed. Listed in CISA KEV. Also confirmed by third-party sources.

Who is affected?

JetBrains / TeamCity affected before 2023.05.4.

What should we do?

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

Overview

In JetBrains TeamCity before 2023.05.4 authentication bypass leading to RCE on TeamCity Server was possible

In JetBrains TeamCity before 2023.05.4 authentication bypass leading to RCE on TeamCity Server was possible

JetBrains Affected
TeamCity
Before 2023.05.4
Published
19 Sep 2023
Exploitation Reported
04 Oct 2023
Attack vector
Remote
Complexity
Low
Privileges
None
User interaction
None

Tags

ransomware metasploit nessus_scanner nuclei_scanner malware cisa

CVE References

Exploitation evidence

Why Previdian marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

CISA

Recorded 04 Oct 2023

A trusted third party reported exploitation.

Used in malware

CISA

Recorded 04 Oct 2023

Malware families have been linked to exploitation of this CVE.

Proof of concept available

GitHub

Recorded 29 Sep 2023

Public scanner or PoC coverage increases practical exploitability.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the Previdian Pro API.

Learn about Pro API access
Source Added
CISA First 2023-10-04 00:00 UTC
Tenable Blog 2026-06-02 14:21 UTC
The Shadowserver 2026-06-04 00:00 UTC

Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets
User-Agents
Callback hosts
0
0
0

Request targets and User-Agents available in Pro. Callback host details available in Enterprise.

Virtual patch status

No Previdian virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

Scanner Artifacts

Scanner and exploit-framework references linked to this CVE.

Scanner Reference Detected
Metasploit https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/multi/http/jetbrains_teamcity_rce_cve_2023_42793.rb 28 Apr 2025
Nuclei https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2023/CVE-2023-42793.yaml 25 Apr 2025
Nessus https://www.tenable.com/plugins/nessus/182690 06 Oct 2023

Risk and context

Severity, weaknesses, and research context

CVSS v3.1

9.8 Critical

Potential damage if exploited. Separate from whether attackers are using it.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS

100.0%

Estimated chance of exploitation in the next 30 days. Previdian's warning comes from evidence, not this score.

Weaknesses

Authentication Bypass Using an Alternate Path or Channel CWE-288 Missing Authentication for Critical Function CWE-306

Recent mention · Tenable Blog

Edge infrastructure under siege: what two independent datasets reveal about who's exploiting your perimeter

A joint Tenable-SentinelOne analysis of 93 CVE-actor attribution pairs reveals that both state-sponsored actors and cybercriminals independently converge on the same edge infrastructure. Special thanks to SentinelOne® Incident Readiness & Response for their contributions to...

Read full advisory

All Mentions

Recent mention · Tenable Blog

Edge infrastructure under siege: what two independent datasets reveal about who's exploiting your perimeter

Tenable Blog · 26 Aug 2026

A joint Tenable-SentinelOne analysis of 93 CVE-actor attribution pairs reveals that both state-sponsored actors and cybercriminals independently converge on the same edge infrastructure. Special thanks to SentinelOne® Incident Readiness & Response for their contributions to this publication.It is the shared attack surface where state-sponsored threat actors and financially motivated criminal groups independently converge — not the province of a single adversary category, and not exclusively a nation-state problem, despite two years of headlines about China-nexus actors targeting Ivanti,...

Recent mention · Tenable Blog

Inside the customer environment: Where threat actors, vulnerabilities, and exposed assets intersect

Tenable Blog · 27 May 2026

Tenable Research has developed a graph-based model linking 600+ threat groups to real-world customer exposures. It reveals which vulnerabilities sit at the intersection of severity, active exploitation, and organizational risk.Key takeawaysThe "patch everything" strategy is dead: Vulnerability prioritization based on exploitation risk offers a path forward. A directed graph model linking 600+ threat actors to vulnerabilities in 7,800 customer environments reveals that 68% of organizations carry at least one CVE previously exploited by a named adversary, and 321 tracked threat groups can...

Potential Proof of Concepts

These PoCs are unverified and could contain malware. Use at your own risk.

JetBrains TeamCity < 2023.05.4 - Remote Code Execution

nuclei · Created Unknown

jetbrains_teamcity_rce_cve_2023_42793

metasploit · Created Unknown

Metasploit module for CVE-2023-42793

Timeline

From disclosure to observed exploitation

  1. 00:00 UTC

    KEV confirmed by The Shadowserver

    Exploitation attested by an external source

  2. 14:21 UTC

    KEV confirmed by Tenable Blog

    Exploitation attested by an external source

  3. 15:02 UTC

    Metasploit module available

    Exploit module available

  4. 15:02 UTC

    Public PoC available

    Public proof-of-concept code published

  5. 00:00 UTC

    Nuclei template available

    Scanner coverage available

  6. 22:24 UTC

    Nessus plugin available

    Scanner coverage available

  7. 00:00 UTC

    Added to CISA KEV

    Listed in the CISA Known Exploited Vulnerabilities catalog

  8. 00:00 UTC

    First public exploitation report

    Exploit observed in malware

  9. 16:57 UTC

    CVE published

    Vulnerability disclosed publicly

  10. 09:48 UTC

    CVE ID reserved

    Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

Start 14-day Pro trial Read API docs
  • Evidence confidence and provenance
  • First-party sensor telemetry
  • PoC and scanner references
  • Affected versions and enrichment
  • Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2023-42793

Sample API response 
{
  "cve_id": "CVE-2023-42793",
  "confidence": "Confirmed",
  "cvss_score": 9.8,
  "cvss_estimated": false,
  "epss_score": 0.99987,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "attempts": 0, "sensors": 0 }
}