| Family | Has Image | Versions |
|---|---|---|
| U-Boot | 5 | |
| U.Rs File Dropper | 1 | |
| U321 Backdoor | 1 | |
| UAY | 1 | |
| UC Downloader | 1 | |
| UDP ShutDown Daemon | 1 | |
| UDPS | 1 | |
| UPIN | 1 | |
| URB Agentr | 1 | |
| URB Downloader | 1 | |
| URCS | 10 | |
| UandMe | 1 | |
| Ubersor | 2 | |
| Ugly Ftp | 1 | |
| Ullysse | 1 | |
| Ultimate 1337 Stealer | 1 | |
| Ultimate Keylogger | 1 | |
| Ultimate Rat | 7 | |
| Ultimate Spy | 1 | |
| Ultimate Trojan | 2 | |
| Ultor | 1 | |
| Ulysses | 4 | |
| Unclear RAT | 1 | |
| Under 7 | 2 | |
| Under Control | 1 | |
| UnderAttack | 1 | |
| Undernet | 1 | |
| Undetectable | 1 | |
| Undetected | 10 | |
| Unify | 5 | |
| UniteMail | 1 | |
| Unitroj | 1 | |
| Universal Control Trojan | 1 | |
| Universal Cracker | 1 | |
| Universal1337 | 2 | |
| Unjustifer | 6 | |
| Unknown Trojans | 3 | |
| Unkound | 1 | |
| Unlimted PW Stealer | 1 | |
| Unlocked | 1 | |
| UnnamedOne Trojan | 0 | |
| Unwind | 1 | |
| Up & Run | 6 | |
| UpFucker Backdoor | 1 | |
| UpKiller RootKit | 1 | |
| Uploader | 3 | |
| Uprising | 3 | |
| UrlDown | 1 | |
| Ursus | 1 | |
| User32 | 1 | |
| uDownload | 1 | |
| uNk Downloader | 1 | |
| unique Bot | 1 |