CVE-2016-6909

Severity: critical (CVSS 9.8 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 49.9% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2016-08-24 · updated 2026-06-17
Weakness: CWE-119

Description

Buffer overflow in the Cookie parser in Fortinet FortiOS 4.x before 4.1.11, 4.2.x before 4.2.13, and 4.3.x before 4.3.9 and FortiSwitch before 3.4.3 allows remote attackers to execute arbitrary code via a crafted HTTP request, aka EGREGIOUSBLUNDER.

Affected products

Fortinet FortiOS (FortiGate): from 4.1.0 before 4.1.11; from 4.2.0 before 4.2.13; from 4.3.0 before 4.3.9 — fixed in 4.1.11, 4.2.13, 4.3.9
Fortinet FortiSwitch: through 3.4.2

How to fix

Upgrade to a fixed version: Fortinet FortiOS (FortiGate) 4.1.11, 4.2.13, 4.3.9. Check the vendor advisory for mitigations.

References

http://fortiguard.com/advisory/FG-IR-16-023
http://packetstormsecurity.com/files/138387/EGREGIOUSBLUNDER-Fortigate-Remote-Code-Execution.html
http://www.securityfocus.com/bid/92523
http://www.securitytracker.com/id/1036643
https://musalbas.com/2016/08/16/equation-group-firewall-operations-catalogue.html
https://www.exploit-db.com/exploits/40276/
http://fortiguard.com/advisory/FG-IR-16-023
http://packetstormsecurity.com/files/138387/EGREGIOUSBLUNDER-Fortigate-Remote-Code-Execution.html
http://www.securityfocus.com/bid/92523
http://www.securitytracker.com/id/1036643
https://musalbas.com/2016/08/16/equation-group-firewall-operations-catalogue.html
https://www.exploit-db.com/exploits/40276/

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