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Known exploited · Fortinet

CVE-2018-13379: Fortinet FortiOS SSL VPN Path Traversal Vulnerability

What it is

Fortinet FortiOS SSL VPN web portal contains a path traversal vulnerability that may allow an unauthenticated attacker to download FortiOS system files through specially crafted HTTP resource requests.

Added November 3, 2021Due May 3, 2022CISA KEV catalog 2026.10.01

Vendor
Fortinet
Product
FortiOS
Added to KEV
November 3, 2021
CISA due date
May 3, 2022
Ransomware use
Known

What CISA requires

Apply updates per vendor instructions.

Forensic triage

No

What to do now

  1. Find every instance of FortiOS you run, including the forgotten ones, and check its version against the vendor advisory.
  2. Apply the vendor's fix or mitigation, before May 3, 2022 if you are bound by CISA's deadline, sooner if it faces the internet.
  3. Assume it was tried against you already: look for signs of exploitation from the date it was added, not from the day you patched.
  4. Until every instance is patched, block the attack at the edge: a WAF in blocking mode stops path traversal attempts.

References

CVE-2018-13379 in the National Vulnerability Database

The Dome

Block it at the edge while you patch

The Dome's WAF runs the OWASP Core Rule Set in blocking mode and stops path traversal attempts before they reach your application.

See the Dome

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Train the engineers who fix it

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Source: CISA Known Exploited Vulnerabilities Catalog (public domain), catalog version 2026.10.01.