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Threats / Fortinet / CVE-2022-42475
CVE-2022-42475 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Fortinet FortiOS vulnerability

Fortinet FortiOS SSL-VPN contains a heap-based buffer overflow allowing unauthenticated remote code execution. The vulnerability is actively exploited in ransomware campaigns.

Verdict

Today item, not a backlog item.

A critical remote code execution flaw in FortiOS SSL-VPN enables unauthenticated attackers to execute arbitrary commands. Active exploitation in ransomware operations and high EPSS score indicate immediate threat to exposed instances.

CISA KEV Yes · 2022-12-133Ransomware use Flagged3EPSS 0.99474 (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
65 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 2022-12-13), flagged for known ransomware use.
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.99474 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Fortinet, FortiOS. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-197 CWE-197.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
Volt Typhoon State-sponsored (PRC)

CISA, NSA and FBI's AA24-038A attributes pre-positioning on US critical-infrastructure IT networks to Volt Typhoon, naming the group's exploitation of public-facing appliance vulnerabilities including the Ivanti Connect Secure (CVE-2024-21887) and Fortinet FortiOS (CVE-2022-42475) CVEs.15

03

Why it matters

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

Front door — unauthenticated access narrative 1

Attacker
I craft malicious SSL-VPN requests to trigger heap buffer overflow and gain code execution without authentication.
Business
Ransomware operators establish initial access to enterprise networks through internet-facing VPN appliances.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I execute arbitrary commands on the compromised FortiOS device to establish persistence and lateral movement.
Business
Attackers pivot from VPN infrastructure into internal networks to deploy encryption malware across critical systems.
3

Lateral reach — past segmentation narrative 3

Attacker
I exfiltrate sensitive data and encrypt business-critical systems to demand ransom payment.
Business
Organizations face operational shutdown, data breach costs, regulatory penalties, and extortion demands.
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)
  • 65 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Public exploit availability
  • 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.