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Threats / Atlassian / CVE-2019-3396
CVE-2019-3396 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-06

Atlassian Confluence Server and Data vulnerability

Atlassian Confluence Server and Data Center contain a server-side template injection vulnerability enabling path traversal and remote code execution.

Verdict

Today item, not a backlog item.

A server-side template injection flaw in Confluence Server and Data Center allows unauthenticated attackers to execute arbitrary code on affected systems. The vulnerability has been actively exploited in ransomware campaigns.

CISA KEV Yes · 2021-11-033Ransomware use Flagged3EPSS 0.94471 (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 2021-11-03), flagged for known ransomware use.
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.94471 — 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: Atlassian, Confluence Server and Data Server. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-22 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-22 · 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 template injection payload targeting the vulnerable template engine.
Business
Attacker gains initial code execution capability on the Confluence server.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I leverage path traversal to access sensitive files and configuration data on the host system.
Business
Sensitive data including credentials and system information is exposed to the attacker.
3

Lateral reach — past segmentation narrative 3

Attacker
I execute arbitrary commands with the privileges of the Confluence process to establish persistence.
Business
Attacker achieves sustained access to the infrastructure for further exploitation.
4

Data at risk — exfiltration narrative 4

Attacker
I deploy ransomware or data exfiltration tools across the compromised environment.
Business
Operations are disrupted, data is encrypted or stolen, and ransom demands are issued.
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 atlassian (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 atlassianCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.