Rapid Reset attack in FortiOS and FortiProxy

Published: 2024-02-09 | Updated: 2024-03-22
Risk High
Patch available YES
Number of vulnerabilities 1
CVE-ID CVE-2023-44487
Exploitation vector Network
Public exploit Vulnerability #1 is being exploited in the wild.
Vulnerable software
Hardware solutions / Routers & switches, VoIP, GSM, etc

Operating systems & Components / Operating system

Vendor Fortinet, Inc

Security Bulletin

This security bulletin contains one high risk vulnerability.

1) Resource exhaustion

EUVDB-ID: #VU81728

Risk: High

CVSSv3.1: 5.1 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:H/RL:O/RC:C]

CVE-ID: CVE-2023-44487

CWE-ID: CWE-400 - Resource exhaustion

Exploit availability: No


The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to improperly control of consumption for internal resources when handling HTTP/2 requests with compressed HEADERS frames. A remote attacker can send a sequence of compressed HEADERS frames followed by RST_STREAM frames and perform a denial of service (DoS) attack, a.k.a. "Rapid Reset".

Note, the vulnerability is being actively exploited in the wild.


Install update from vendor's website.

Vulnerable software versions

FortiProxy: 7.0.0 - 7.4.1

FortiOS: 7.0.0 - 7.4.2

External links


Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected device in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

Yes. This vulnerability is being exploited in the wild.