What is CVE-2023-42793?

CVE-2023-42793 is a critical-severity vulnerability in Jetbrains Teamcity, classified under Authentication Bypass Using an Alternate Path or Channel. CVSS score: 9.8/10. Published 2023-09-19.

How severe is CVE-2023-42793?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2023-42793 known to be exploited?

Yes. CVE-2023-42793 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2023-10-04), indicating it is being actively exploited. 54 public proof-of-concept repositories are indexed.

Auth bypass in Jetbrains Teamcity

CVE-2023-42793

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

Published 2023-09-19 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 1.000 (100.0th percentile), scored 2026-10-04.

Very high probability of exploitation in the next 30 days — among the top 0.1% most-likely-to-be-exploited CVEs. 100th percentile — 100.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 1.000 · newest: 1.000 · change: -0.000

Affected products

Jetbrains Teamcity — versions 0

Weakness classification (CWE)

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on 2023-10-04. CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: 2023-10-25.

Required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

Known ransomware campaign use: yes.

Public proof-of-concept exploits

References

www.jetbrains.com/privacy-security/issues-fixed/ (Vendor Advisory)
blog.jetbrains.com/teamcity/2023/09/cve-2023-42793-vulnerability-post-mortem/ (Vendor Advisory)
packetstormsecurity.com/files/174860/JetBrains-TeamCity-Unauthenticated-Remote-… (Exploit, VDB Entry, Third Party Advisory)
attackerkb.com/topics/1XEEEkGHzt/cve-2023-42793 (Third Party Advisory)
www.securityweek.com/recently-patched-teamcity-vulnerability-exploited-to-hack-… (Press/Media Coverage)
www.rapid7.com/blog/post/2023/09/25/etr-cve-2023-42793-critical-authentication-… (Third Party Advisory, Broken Link)
www.sonarsource.com/blog/teamcity-vulnerability/ (Exploit, Third Party Advisory)
134c704f-9b21-4f2e-91b3-4a467353bcc0 (US Government Resource)

Frequently asked questions

What is CVE-2023-42793?: CVE-2023-42793 is a critical-severity vulnerability in Jetbrains Teamcity, classified under Authentication Bypass Using an Alternate Path or Channel. CVSS score: 9.8/10. Published 2023-09-19.
How severe is CVE-2023-42793?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2023-42793 known to be exploited?: Yes. CVE-2023-42793 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2023-10-04), indicating it is being actively exploited. 54 public proof-of-concept repositories are indexed.