CVE-2018-13383mediumunder attackransomwareCWE-787

CVE-2018-13383: medium-severity vulnerability in Fortinet FortiOS and FortiProxy

Published · Updated

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55Vexday Risk Score

Prioritize patching. It under exploitation confirmed by CISA.

ssvc Attendcvss 4.3epss 32%
from disclosure to weapon
Published on NVDMay 29
CISA KEV+957d
Action required by CISAfederal deadline: 2022-07-10

Apply updates per vendor instructions.

In short

FortiOS and FortiProxy SSL VPN web portals have a memory overflow vulnerability that can crash the VPN service when processing certain malicious web page content. Attackers with access to the portal can trigger this crash, temporarily disrupting VPN service for other users.

Technical detail

A heap buffer overflow exists in the SSL VPN web portal's JavaScript href handling mechanism when proxying webpages across multiple FortiOS and FortiProxy versions. An authenticated attacker can exploit this via specially crafted JavaScript href data to cause a denial of service by terminating the SSL VPN web service. The vulnerability requires the attacker to have valid portal access and the vulnerable version to be deployed.

Summary generated and translated by AI from the official description.

The full analysis of this CVE is available in Portuguese →

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.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
Affected products
Fortinet · Fortinet FortiOS and FortiProxy
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