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Threats / Fortinet / CVE-2018-13374
CVE-2018-13374 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Fortinet FortiOS and FortiADC vulnerability

Fortinet FortiOS and FortiADC contain an improper access control flaw allowing attackers to extract LDAP server credentials by redirecting connectivity test requests to a rogue LDAP server.

Verdict

Today item, not a backlog item.

An attacker can intercept or redirect LDAP server connectivity tests to capture plaintext credentials configured in FortiGate devices, leading to unauthorized access to directory services and lateral movement within enterprise networks.

CISA KEV Yes · 2022-09-083Ransomware use Flagged3EPSS 0.38088 (verify live)4
01

Is it exploitable?

— the evidence, ranked above the score
Reported exploitation
9 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 2022-09-08), flagged for known ransomware use.
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.38088 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Fortinet, FortiOS and FortiADC. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-732 Incorrect Permission Assignment — weakness family: Authorization / access control.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
WeaknessCWE-732 · Incorrect Permission AssignmentAuthorization / access control
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 craft a rogue LDAP server and position it to intercept or receive a connectivity test request from a FortiGate device.
Business
Attacker gains access to LDAP credentials, enabling compromise of directory services and user authentication systems.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I capture the LDAP login credentials transmitted in the test request without encryption or validation.
Business
Compromised directory credentials allow lateral movement across the enterprise and access to sensitive user and resource information.
3

Lateral reach — past segmentation narrative 3

Attacker
I use the extracted credentials to authenticate to the legitimate LDAP server and enumerate users and groups.
Business
Attacker establishes persistent access to identity infrastructure, increasing risk of data exfiltration and further network compromise.
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)
  • 9 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Catalogued by fortinet (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 fortinetCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.