Last Modified: Oct 08, 2025
Affected Product(s):
BIG-IP TMOS
Known Affected Versions:
15.1.0, 15.1.0.1, 15.1.0.2, 15.1.0.3, 15.1.0.4, 15.1.0.5, 15.1.1, 15.1.2, 15.1.2.1, 15.1.3, 15.1.3.1, 15.1.4, 15.1.4.1, 15.1.5, 15.1.5.1, 15.1.6, 15.1.6.1, 15.1.7, 15.1.8, 15.1.8.1, 15.1.8.2, 15.1.9, 15.1.9.1, 15.1.10, 15.1.10.2, 15.1.10.3, 15.1.10.4, 15.1.10.5, 15.1.10.6, 16.1.0, 16.1.1, 16.1.2, 16.1.2.1, 16.1.2.2, 16.1.3, 16.1.3.1, 16.1.3.2, 16.1.3.3, 16.1.3.4, 16.1.3.5, 16.1.4, 16.1.4.1, 16.1.4.2, 16.1.4.3, 16.1.5, 16.1.5.1, 16.1.5.2, 16.1.6, 17.1.0, 17.1.0.1, 17.1.0.2, 17.1.0.3, 17.1.1, 17.1.1.1, 17.1.1.2, 17.1.1.3, 17.1.1.4, 17.1.2, 17.1.2.1, 17.1.2.2
Opened: Sep 22, 2025 Severity: 2-Critical
When downloading UCS files using the BIG-IP REST API with clients such as PowerShell 7, downloaded files are larger than expected and contain duplicate or corrupted data. The MD5 checksum of the downloaded file does not match the source UCS file on the BIG-IP system. This is due to the REST service returning the same portion of the file for every chunk request, resulting in failed or unusable UCS restore attempts
UCS file downloads via REST API are incomplete and corrupted. MD5 checksum mismatch prevents UCS archive validation or restore. Automated backups or migrations using REST API may fail. Potential risk of data loss if corrupted UCS files are used for restore.
Affected when downloading UCS files over the REST API (using HTTP Range headers) from BIG-IP. Most commonly seen with PowerShell 7 and other clients that download files in chunks. Not observed with PowerShell 5 or when using SCP/SFTP. Occurs on affected TMOS versions before the implementation of the fix.
Use alternate file transfer methods such as SCP or SFTP to download UCS files directly from /var/local/ucs/ on the BIG-IP system.
None