BugZero | Fortinet BugID 1252663 - On FortiGate D-series devices running older BIOS v...

Fortinet - Defect ID: 1252663

On FortiGate D-series devices running older BIOS versions, the serial number changes to FGT0000000000001 after upgrading to FortiOS 7.4.10, 7.4.11, 7.6.5, and 7.6.6

Fortinet - Defect ID: 1252663

On FortiGate D-series devices running older BIOS versions, the serial number changes to FGT0000000000001 after upgrading to FortiOS 7.4.10, 7.4.11, 7.6.5, and 7.6.6

Last updated on June 2nd, 2026

BugZero Risk Score
8.6 High

Overall: 8.6

Lifecycle: 10.0

Community: 7.3

What is the BugZero Risk Score?

Fortinet Integration

Learn more about where this data comes from

Fortinet Integration

Learn more

Bug Scrub Advisor

Streamline upgrades with automated vendor bug scrubs

Bug Scrub Advisor

Learn more

BugZero Enterprise

Wish you caught this bug sooner? Get proactive today.

BugZero Enterprise

Learn more

Bug Details

Priority: Unspecified
Status: Fixed
Impacted Service: Existing Known IssuesModel SpecificUpgrade

Description

On FortiGate D-series devices running older BIOS versions, the serial number changes to FGT0000000000001 after upgrading to FortiOS 7.4.10,7.4.11,7.6.5,7.6.6. On FortiGate D-series devices running older BIOS versions, the serial number changes to FGT0000000000001 after upgrading to FortiOS 7.4.10, 7.4.11, 7.6.5, and 7.6.6.

Change history

2025-12-11 Added: 7.4.10, 7.4.11, 7.6.5, 7.6.6

Links

Relevant Products

Click on a version to see all relevant bugs

Affected versions:7.4.10, 7.4.11, 7.6.5, 7.6.6

Fixed versions: 7.4.12, 7.6.7, 8.0.0

Relevant Products

Click on a version to see all relevant bugs

Affected versions:7.4.10, 7.4.11, 7.6.5, 7.6.6

Fixed versions: 7.4.12, 7.6.7, 8.0.0

Top Fortinet Defects

8.6Defect ID: 1240901
PCI scan fails when using HTTP/1.0 on the SSLVPN port
8.6Defect ID: 1252663
On FortiGate D-series devices running older BIOS versions, the serial number changes to FGT0000000000001 after upgrading to FortiOS 7.4.10, 7.4.11, 7.6.5, and 7.6.6
8.5Defect ID: 1213247
504 Gateway Timeout shown when a virtual-server configured in full mode connects to a HTTPS server that only supports TLS <= 1.2 and which also only supports using SHA1 for signatures
8.4Defect ID: 1260236
Unexpected power off events occur in FortiGate 70G when configured in HA Active/Passive mode with wireless traffic
8.4Defect ID: 1259458
Intermittent reboot of FortiGate-71G caused by an error condition in the IPS engine

Ready to prevent the next vendor outage?

Get a demo

Fortinet - Defect ID: 1252663

On FortiGate D-series devices running older BIOS versions, the serial number changes to FGT0000000000001 after upgrading to FortiOS 7.4.10, 7.4.11, 7.6.5, and 7.6.6

Fortinet - Defect ID: 1252663

On FortiGate D-series devices running older BIOS versions, the serial number changes to FGT0000000000001 after upgrading to FortiOS 7.4.10, 7.4.11, 7.6.5, and 7.6.6

Last updated on June 2nd, 2026

BugZero Risk Score8.6 High

Bug Details

Links

Top Fortinet Defects

Ready to prevent the next vendor outage?

BugZero Risk Score
8.6 High