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Threats / JetBrains / CVE-2023-42793
CVE-2023-42793 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

JetBrains TeamCity vulnerability

JetBrains TeamCity authentication bypass vulnerability allows remote code execution on TeamCity Server. Actively exploited in ransomware campaigns.

Verdict

Today item, not a backlog item.

An unauthenticated attacker can bypass authentication controls in TeamCity and achieve remote code execution, leading to full server compromise. This vulnerability is being actively exploited in ransomware operations.

CISA KEV Yes · 2023-10-043Ransomware use Flagged3EPSS 0.99979 (verify live)4Exploit Weaponized · public PoC5
01

Is it exploitable?

— the evidence, ranked above the score
Exploit available
Fully weaponized — public exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
Reported exploitation
871 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2023-10-04), flagged for known ransomware use.
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.99979 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: JetBrains, TeamCity. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-288 Auth Bypass via Alternate Path — weakness family: Authentication.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
02

Who’s exploiting it?

— attribution turns risk into urgency
Attribution not established

No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.

03

Why it matters

— the attack path, told twice: adversary, then board
1

Front door — unauthenticated access narrative 1

Attacker
I bypass authentication mechanisms in TeamCity without valid credentials.
Business
Access controls fail to protect the CI/CD infrastructure from unauthorized entry.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I execute arbitrary code on the TeamCity Server following successful authentication bypass.
Business
The build and deployment pipeline becomes a pivot point for lateral movement and data exfiltration.
3

Lateral reach — past segmentation narrative 3

Attacker
I establish persistence and deploy ransomware payloads across the infrastructure.
Business
Critical development and production systems are encrypted, halting operations and triggering financial extortion.
04

What to do

— defensible action
  • Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05

Coverage & confidence

— what we know, and what we don’t

Established (cited)

  • KEV listing (CISA)
  • Ransomware-use flag (CISA)
  • EPSS probability (FIRST)
  • Weaponized exploit available (VulnCheck)
  • 871 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Public exploit availability
  • Catalogued by JetBrains (CNA)
  • Coverage gaps — stated, not hidden

  • No EUVD / GCVE mirror in feed — single-authority dependency for the identifier.
  • EPSS & exposure are time-varying; verify live at the source.
  • Threat-actor attribution not established from feed data — absence of a name is not absence of compromise.
  • No finder/reporter credit recorded in the public CVE entry — the work behind this find is unattributed.
  • Disclosure & credit2
    Catalogued by JetBrainsCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.