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Threats / JetBrains / CVE-2024-27199
CVE-2024-27199 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-06

JetBrains TeamCity vulnerability

JetBrains TeamCity contains a relative path traversal vulnerability enabling limited admin actions. Actively exploited in ransomware campaigns.

Verdict

Today item, not a backlog item.

A path traversal flaw in TeamCity allows attackers to bypass access controls and perform restricted administrative operations. Active exploitation in ransomware campaigns indicates high real-world risk despite functional limitations.

CISA KEV Yes · 2026-04-203Ransomware use Flagged3EPSS 0.90931 (verify live)4
01

Is it exploitable?

— the evidence, ranked above the score
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2026-04-20), flagged for known ransomware use.
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.90931 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
FIRST EPSS ↗High
Severity / affected
Affected: JetBrains, TeamCity. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-23 Relative Path Traversal — weakness family: Path traversal / file.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
WeaknessCWE-23 · Relative Path TraversalPath traversal / file
02

Who’s exploiting it?

— attribution turns risk into urgency
Attribution not established

No threat-actor attribution is established from the public feed 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 craft a malicious request using relative path sequences to traverse the file system and access restricted administrative functions.
Business
Unauthorized administrative capabilities are exposed, creating a foothold for privilege escalation and system compromise.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I leverage the path traversal to perform limited admin actions without proper authentication or authorization checks.
Business
Access controls fail, allowing attackers to modify configurations, create accounts, or alter deployment pipelines.
3

Lateral reach — past segmentation narrative 3

Attacker
I use the compromised admin access to establish persistence or deploy ransomware payloads across the CI/CD infrastructure.
Business
Build systems and deployment infrastructure become vectors for enterprise-wide ransomware distribution and operational shutdown.
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)
  • CWE weakness mapping (NVD)
  • 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.