CVE-2018-13379
Fortinet FortiOS SSL VPN Path Traversal Vulnerability
- Critical 9.1
- Exploited: added to CISA KEV 3 Nov 2021
- Used in ransomware campaigns
Description
An Improper Limitation of a Pathname to a Restricted Directory ("Path Traversal") in Fortinet FortiOS 6.0.0 to 6.0.4, 5.6.3 to 5.6.7 and 5.4.6 to 5.4.12 and FortiProxy 2.0.0, 1.2.0 to 1.2.8, 1.1.0 to 1.1.6, 1.0.0 to 1.0.7 under SSL VPN web portal allows an unauthenticated attacker to download system files via special crafted HTTP resource requests.
Key facts
- Published
- 4 Jun 2019
- Last changed
- 21 Oct 2025
- Assigned by
- fortinet
- KEV added
- 3 Nov 2021
- KEV fix due
- 3 May 2022
- Used in ransomware
- Yes, according to CISA
- EPSS
- 99.999% likely to be exploited in the next 30 days, higher than 99.994% of CVEs (scores for 15 Nov 2026)
- SSVC (CISA)
- Exploitation: active; Automatable: yes; Technical impact: partial
Severity scores
Each score is shown as its source gave it. They are not averaged or merged.
- 9.1CVSS 3.1, Criticalfrom the CNA (fortinet)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
What to do
- Apply updates per vendor instructions.CISA KEV required action
Historical context and remediation
This reference retains the original CVE publication date. A recent record update does not mean a new attack occurred.
No separately sourced impact summary is available on this page yet. Consult the description, version data and dated exploitation evidence.
Version statuses below come from the CNA. An “unaffected” version is not necessarily a currently supported release or proof of a patch date. EPSS is a dated risk estimate, not a count of historical attacks.
Affected products
| Vendor | Product | Versions |
|---|---|---|
| Fortinet | Fortinet FortiOS, FortiProxy |
|
Timeline
- 4 Jun 2019 Published
- 3 Nov 2021 CVE-2018-13379 added to CISA KEV
- 3 Nov 2021 Added to the CISA KEV catalogue
Weakness
Practice this bug class
HackZoneLabs has a hands-on lab on Path traversal (CWE-22).