SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2017-17543

Users' VPN authentication credentials are unsafely encrypted in Fortinet FortiClient for Windows 5.6.0 and below versions, FortiClient for Mac OSX 5.6.0 and below versions and FortiClient SSLVPN Client for Linux 4.4.2335 and below versions, due to the…

HIGH 7.5EPSS 0.44%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.44%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

Users' VPN authentication credentials are unsafely encrypted in Fortinet FortiClient for Windows 5.6.0 and below versions, FortiClient for Mac OSX 5.6.0 and below versions and FortiClient SSLVPN Client for Linux 4.4.2335 and below versions, due to the use of a static encryption key and weak encryption algorithms.

CVSS 3.0
7.5 HIGHCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS
0.44% probability · 38th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-326
Affected
fortinet/forticlient · fortinet/forticlient sslvpn client
Source
psirt@fortinet.com
EPSS trend
0%3%5%27 October 2026: 0.44%27 October 202627 October 2026

EPSS 0.4% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.