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  3. CVE-2022-42475
Exploited in the wildUsed by ransomwareVPNs, firewalls & gatewaysWork IT

CVE-2022-42475 Fortinet FortiOS: memory-safety flaw

In plain words: The program mishandles the memory it uses to keep track of data. A specially made input can scramble that memory. Usually lets an attacker crash the program or run their own code with its permissions.

Confirmed exploited by CISA on · US federal patch deadline Jan 3, 2023

What to do

  1. Install Fortinet's security update for FortiOS. If no update exists, follow the vendor's workaround or stop using the product until one ships.
  2. Patch edge devices first — attackers often start scanning for them within hours of a fix.
  3. Never expose the device's admin page to the internet.
  4. After patching a device that was exposed, follow the vendor's compromise checks, end active sessions and change passwords.

Read Fortinet's advisory ↗

Who is affected

Work IT. Aimed mostly at company systems — you are affected through the companies you use, not your own phone.

What's at risk: They face the internet and guard the whole network, so a flaw here can hand attackers a way in — and these devices usually run no antivirus, so break-ins go unnoticed.

The details

Official name
Fortinet FortiOS Heap-Based Buffer Overflow Vulnerability
Product
Fortinet FortiOS
CISA description
Multiple versions of Fortinet FortiOS SSL-VPN contain a heap-based buffer overflow vulnerability which can allow an unauthenticated, remote attacker to execute arbitrary code or commands via specifically crafted requests.
Type of flaw
Memory-safety flaw (CWE-197)
Confirmed exploited
Dec 13, 2022 — known to be used in ransomware attacks
US federal patch deadline
Jan 3, 2023

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Answering about CVE-2022-42475 ·

Questions about CVE-2022-42475

Is CVE-2022-42475 being exploited?

Yes. CISA added CVE-2022-42475 to its Known Exploited Vulnerabilities catalog on Dec 13, 2022, which means there is reliable evidence of real-world attacks, including by ransomware groups.

How do I fix CVE-2022-42475?

Install Fortinet's security update for FortiOS. If no update exists, follow the vendor's workaround or stop using the product until one ships. Patch edge devices first — attackers often start scanning for them within hours of a fix.

Am I affected by CVE-2022-42475?

Only if you use Fortinet FortiOS. Aimed mostly at company systems — you are affected through the companies you use, not your own phone.

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