UpHeron
All vulnerabilities

Servers and applications

CVE-2018-13383

A heap buffer overflow in Fortinet FortiOS 6.0.0 through 6.0.4, 5.6.0 through 5.6.10, 5.4.0 through 5.4.12, 5.2.14 and earlier and FortiProxy 2.0.0, 1.2.8 and earlier in the SSL VPN web portal may cause the SSL VPN web service termination for logged in users due to a failure to properly handle javascript href data when proxying webpages.

Actively exploited: CISA added it to its Known Exploited Vulnerabilities catalog on 10 Jan 2022.

Severity
Medium 6.5
Published
29 May 2019
Last changed
17 Jun 2026
Added to UpHeron
1 Nov 2026
Fixed in
1.2.9, 5.2.15, 5.4.13, 5.6.11, 6.0.5
Exploit chance
31% in the next 30 daysHigher than 98% of CVEs. EPSS by FIRST, 10 Nov 2026
Sources
NVD

Affected software

SoftwareAffected versions
Fortinet FortiProxyServers and applications · cpe:a:fortinet:fortiproxy
  • Every version before 1.2.9
  • Version 2.0.0
Fortinet FortiOSServers and applications · cpe:o:fortinet:fortios
  • From 5.2.0 before 5.2.15
  • From 5.4.0 before 5.4.13
  • From 5.6.0 before 5.6.11
  • From 6.0.0 before 6.0.5

Known exploited

CISA name
Fortinet FortiOS and FortiProxy Out-of-bounds Write
Required action
Apply updates per vendor instructions.
Due for US agencies
10 Jul 2022
Used in ransomware
Yes, known

References

  • NVD https://nvd.nist.gov/vuln/detail/CVE-2018-13383
  • CVE.org https://www.cve.org/CVERecord?id=CVE-2018-13383