basicsecurity.net
Proof, not just disclosure.
Threats / Atlassian / CVE-2019-3398
CVE-2019-3398 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Atlassian Confluence Server and Data Center vulnerability

Atlassian Confluence Server and Data Center contain a path traversal vulnerability in the downloadallattachments resource that allows privileged remote attackers to write files, potentially enabling remote code execution.

Verdict

Today item — known-exploited.

A path traversal flaw in Confluence's downloadallattachments endpoint permits authenticated attackers to escape directory restrictions and place arbitrary files on the server, creating a direct pathway to code execution and system compromise.

CISA KEV Yes · 2021-11-033EPSS 0.97153 (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
1 independent public report of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
cisa.gov ↗Confirmed
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.97153 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Atlassian, Confluence Server and Data Center. 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 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 identify that the downloadallattachments resource fails to properly validate file paths, allowing me to use traversal sequences to write files outside intended directories.
Business
Attackers gain ability to place malicious files on production infrastructure, directly threatening operational continuity and data integrity.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I craft a request with path traversal payloads to write executable code to a location where the Confluence process will execute it.
Business
Remote code execution on Confluence servers enables attackers to pivot into internal networks, exfiltrate sensitive data, and establish persistent access.
3

Lateral reach — past segmentation narrative 3

Attacker
I execute arbitrary commands with the privileges of the Confluence application process to establish control over the affected system.
Business
Full compromise of Confluence infrastructure results in exposure of collaborative documents, credentials, and integration points used across the organization.
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)
  • EPSS probability (FIRST)
  • Weaponized exploit available (VulnCheck)
  • 1 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Public exploit availability
  • 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.