Remote code execution in FortiWeb Proxyd
| Risk | High |
| Patch available | YES |
| Number of vulnerabilities | 1 |
| CVE-ID | CVE-2021-42756 |
| CWE-ID | CWE-121 |
| Exploitation vector | Network |
| Public exploit | N/A |
| Vulnerable software Subscribe |
Fortinet FortiWeb Server applications / Remote management servers, RDP, SSH |
| Vendor | Fortinet, Inc |
Security Bulletin
This security bulletin contains one high risk vulnerability.
1) Stack-based buffer overflow
EUVDB-ID: #VU84879
Risk: High
CVSSv3.1: 8.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]
CVE-ID: CVE-2021-42756
CWE-ID:
CWE-121 - Stack-based buffer overflow
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to a boundary error in the proxy daemon. A remote unauthenticated attacker can send a specially crafted HTTP request to the system, trigger a stack-based buffer overflow and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
MitigationInstall updates from vendor's website.
Vulnerable software versionsFortinet FortiWeb: 5.6.0 - 6.4.2
External linkshttp://www.fortiguard.com/psirt/FG-IR-21-186
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 application in order to exploit this vulnerability.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.
