CVE-2024-21762

critical

Description

A out-of-bounds write in Fortinet FortiOS versions 7.4.0 through 7.4.2, 7.2.0 through 7.2.6, 7.0.0 through 7.0.13, 6.4.0 through 6.4.14, 6.2.0 through 6.2.15, 6.0.0 through 6.0.17, FortiProxy versions 7.4.0 through 7.4.2, 7.2.0 through 7.2.8, 7.0.0 through 7.0.14, 2.0.0 through 2.0.13, 1.2.0 through 1.2.13, 1.1.0 through 1.1.6, 1.0.0 through 1.0.7 allows attacker to execute unauthorized code or commands via specifically crafted requests

From the Tenable Blog

CVE-2024-21762: Critical Fortinet FortiOS Out-of-Bound Write SSL VPN Vulnerability

Published: 2024-02-09

Fortinet warns of “potentially” exploited flaw in the SSL VPN functionality of FortiOS, as government agencies warn of pre-positioning by Chinese state-sponsored threat actors in U.S. critical infrastructure through exploitation of known vulnerabilities

References

https://www.securityweek.com/critical-arista-velocloud-orchestrator-vulnerability-exploited-as-zero-day/

https://thehackernews.com/2026/06/new-sharkloader-malware-deploys-cobalt.html

https://securelist.com/strikeshark-campaign/120326/

https://www.infosecurity-magazine.com/news/operation-escaneo-cloudsek-latam/

https://cloud.google.com/blog/topics/threat-intelligence/ransomware-ttps-shifting-threat-landscape/

https://www.securityweek.com/fortinet-patches-high-severity-vulnerabilities/

https://www.greynoise.io/blog/unmasking-cisas-hidden-kev-ransomware-updates

https://securelist.com/malware-report-q2-2025-pc-iot-statistics/117421/

https://cybelangel.com/blog/qilin-ransomware-tactics-attack/

https://databreaches.net/2025/07/12/qilin-emerged-as-the-most-active-group-exploiting-unpatched-fortinet-vulnerabilities/

https://www.infosecurity-magazine.com/news/automation-vulnerability/

https://www.hipaajournal.com/qilin-ransomware-group-exploiting-critical-fortinet-flaws/

https://thehackernews.com/2025/06/former-black-basta-members-use.html

https://www.bleepingcomputer.com/news/security/critical-fortinet-flaws-now-exploited-in-qilin-ransomware-attacks/

https://securityaffairs.com/178736/hacking/attackers-exploit-fortinet-flaws-to-deploy-qilin-ransomware.html

https://www.securityweek.com/threat-actor-allegedly-selling-fortinet-firewall-zero-day-exploit/

https://www.darkreading.com/vulnerabilities-threats/fortinet-zero-day-arbitrary-code-execution

https://www.cisa.gov/news-events/alerts/2025/04/11/fortinet-releases-advisory-new-post-exploitation-technique-known-vulnerabilities

https://www.bleepingcomputer.com/news/security/fortinet-hackers-retain-access-to-patched-fortigate-vpns-using-symlinks/

https://thehackernews.com/2025/04/fortinet-warns-attackers-retain.html

https://isc.sans.edu/diary/rss/30762

https://www.bleepingcomputer.com/news/security/critical-fortinet-flaw-may-impact-150-000-exposed-devices/

https://www.bleepingcomputer.com/news/security/new-fortinet-rce-flaw-in-ssl-vpn-likely-exploited-in-attacks/

https://github.com/h4x0r-dz/CVE-2024-21762

https://www.tenable.com/blog/cve-2026-35616-fortinet-forticlientems-improper-access-control-vulnerability-exploited-in-the

https://www.tenable.com/blog/operation-epic-fury-why-exposure-data-changes-everything-about-irans-cyber-kinetic-campaign

https://www.tenable.com/blog/cve-2025-64155-exploit-code-released-for-critical-fortinet-fortisiem-command-injection

https://www.tenable.com/blog/cve-2025-64446-fortinet-fortiweb-zero-day-path-traversal-vulnerability-exploited-in-the-wild

https://www.tenable.com/blog/cve-2025-25256-proof-of-concept-released-for-critical-fortinet-fortisiem-command-injection

https://www.tenable.com/blog/cve-2025-32756-zero-day-vulnerability-in-multiple-fortinet-products-exploited-in-the-wild

https://www.tenable.com/blog/verizon-2025-dbir-tenable-research-collaboration

https://www.tenable.com/blog/cve-2024-55591-fortinet-authentication-bypass-zero-day-vulnerability-exploited-in-the-wild

https://www.tenable.com/blog/cve-2023-48788-critical-fortinet-forticlientems-sql-injection-vulnerability

https://www.tenable.com/blog/cve-2024-21762-critical-fortinet-fortios-out-of-bound-write-ssl-vpn-vulnerability

https://github.com/jkhda456/quickCVE

https://github.com/belky-me/vamp-cve-oracle

https://github.com/Vampsecure-Labs/vamp-cve-oracle

https://github.com/belky-me/vamp-forticheck

https://github.com/Vampsecure-Labs/vamp-forticheck

https://github.com/eavil666/cve-poc-mapper

https://github.com/godly-raam/CVE-Research-Portfolio

https://github.com/ykrishhh/cve-pocs

https://github.com/Sxmpl3/CVE-2024-21762-Safe-Check

https://github.com/ericrihm/edge-security-ground-truth

https://github.com/sreenidhi-n/socrates

https://github.com/Arshdeep030/CVE-Exploitation-Intelligence

https://github.com/user70616E6461/phantom-intel

https://github.com/vanshkamra12/CyberThreat-Intel-LLM

https://github.com/kholcomb/threatbridge

https://github.com/RosieDomenech/cve-threat-profiler

https://github.com/Naim-ch/cve-enrichment-api

https://github.com/Naim-ch/CVE-Enrichment-API

https://github.com/J3ff-R3y/network-scanner-cmdb

https://github.com/badchars/cve-mcp

https://github.com/Kalyan-Adhikari/CVE-Checker-Local

https://github.com/Leegreen305/CVE-Threat-Intelligence-Tracker

https://github.com/yanitedhacker/cve-threat-radar

https://github.com/nikjohn7/VulnPulse

https://github.com/0x13-ByteZer0/CVE-2024-21762

https://github.com/Kimiya00/security-threat-analyzer

https://github.com/Ereline/CVE-Search

https://github.com/Disseminator/Poc_CVEs

https://github.com/vorotilovaawex/CVE-2024-21762_POC

https://github.com/r4p3c4/CVE-2024-21762-Exploit-PoC-Fortinet-SSL-VPN-Check

https://github.com/cleverg0d/CVE-2024-21762-Checker

https://github.com/tr1pl3ight/CVE-2024-21762-POC

https://github.com/Instructor-Team8/CVE-2024-20291-POC

https://github.com/BetterCzz/CVE-2024-20291-POC

https://github.com/greandfather/CVE-2024-20291-POC

https://github.com/BishopFox/cve-2024-21762-check

https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2024-21762

https://fortiguard.com/psirt/FG-IR-24-015

Details

Source: Mitre, NVD

Published: 2024-02-09

Updated: 2026-08-04

Known Exploited Vulnerability (KEV)

Risk Information

CVSS v2

Base Score: 10

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C

Severity: Critical

CVSS v3

Base Score: 9.8

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Severity: Critical

EPSS

EPSS: 0.84285

Vulnerability Watch

Tenable Research has classified this CVE under the following Vulnerability Watch classification, which includes active and historical (inactive) classifications. You can learn more about these classifications on our blog.

Vulnerability of Interest

Detections

Analytics