AI description
CVE-2019-5591 is a default configuration vulnerability that affects FortiOS. It exists because, under the default configuration, FortiGate SSL VPN does not verify the certificate when a Lightweight Directory Access Protocol (LDAP) server sends a connection request. An unauthenticated attacker on the same subnet could exploit this vulnerability by impersonating the LDAP server and connecting to a vulnerable FortiGate device. Successful exploitation could allow the attacker to intercept sensitive information intended for a legitimate LDAP server.
- Description
- A Default Configuration vulnerability in FortiOS may allow an unauthenticated attacker on the same subnet to intercept sensitive information by impersonating the LDAP server.
- Source
- psirt@fortinet.com
- NVD status
- Analyzed
- Products
- fortios
CVSS 3.1
- Type
- Primary
- Base score
- 6.5
- Impact score
- 3.6
- Exploitability score
- 2.8
- Vector string
- CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- Severity
- MEDIUM
CVSS 2.0
- Type
- Primary
- Base score
- 3.3
- Impact score
- 2.9
- Exploitability score
- 6.5
- Vector string
- AV:A/AC:L/Au:N/C:P/I:N/A:N
Data from CISA
- Vulnerability name
- Fortinet FortiOS Default Configuration Vulnerability
- Exploit added on
- Nov 3, 2021
- Exploit action due
- May 3, 2022
- Required action
- Apply updates per vendor instructions.
- Hype score
- Not currently trending
Ransomware vulns with highest exploit likelihood ⬆️ (past 30d): - CVE-2021-26857 (Exchange On-Pre..) +210.76% - CVE-2022-26500 (Veeam Backup & ..) +24.70% - CVE-2023-27532 (Veeam Backup & ..) +17.62% - CVE-2022-41352 (Zimbra Zimbra C..) +16.52% - CVE-2019-5591 (Forti
@DefusedCyber
29 Sept 2025
33921 Impressions
50 Retweets
256 Likes
138 Bookmarks
3 Replies
2 Quotes
Ransomware vulns with highest exploit likelihood ⬆️ (past 30d): - CVE-2025-53770 (SharePoint..) +86627.50% - CVE-2019-5591 (FortiOS..) +44.14% - CVE-2021-26857 (Exchange On-Pre..) +32.05% - CVE-2024-42057 (Zyxel Firewall..) +29.73% - CVE-2021-27101 (Accellion File ..) +23.48
@DefusedCyber
11 Aug 2025
652 Impressions
2 Retweets
8 Likes
4 Bookmarks
0 Replies
1 Quote
Ransomware vulns with highest exploit likelihood ⬆️ (past 30d): - CVE-2025-53770 (SharePoint..) +3700.00% - CVE-2019-6693 (FortiOS..) +159.30% - CVE-2019-5591 (FortiOS..) +44.14% - CVE-2024-42057 (Zyxel Firewall..) +33.61% - CVE-2018-13374 (FortiOS..) +30.01%
@DefusedCyber
23 Jul 2025
1200 Impressions
2 Retweets
9 Likes
3 Bookmarks
0 Replies
1 Quote
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