Did you just find a download or a file on your computer that has a digital signature from Acai Tech Ltd? Some of the security products refers to the detected files as Gen:Variant.Graftor.160428 and WS.Reputation.1. The detection rate for the Acai Tech Ltd files collected here is 10%. Please read on for more details.
You will probably see Acai Tech Ltd when double-clicking to run the file. The publisher name is then displayed as the "Verified publisher" in the UAC dialog as the screenshot shows:

You can view additional details from the Acai Tech Ltd certificate with the following steps:
Here's a screenshot of a file that has been signed by Acai Tech Ltd:

As you can see in the screenshot above, Windows reports that "This digital signature is OK". This means that the file has been published by Acai Tech Ltd and that no one has tampered with the file.
If you click the View Certificate button shown in the screenshot above, you can examine all the details of the certificate, such as when it was issued, who issued the certificate, how long it is valid, etc. You can also view the address for Acai Tech Ltd, such as the street name, city and country.
COMODO RSA Code Signing CA has issued the Acai Tech Ltd certificates. You can also view the details of the issuer by clicking the View Certificate button shown in the screenshot above.
The following are the Acai Tech Ltd files I've gathered, thanks to the FreeFixer users.
| Detection Ratio | File Name |
|---|---|
| 1/54 | dsrvprn.exe |
| 2/55 | lsdprn.exe |
| 6/56 | lsdprn.exe |
| 4/55 | bop64.dll |
| 15/55 | bntf.exe |
Here's the detection names for the Acai Tech Ltd files. I've grouped the detection names by each scanner engine. Thanks to VirusTotal for the scan results.
| Scanner | Detection Names |
|---|---|
| AVware | Trojan.Win32.Generic!BT |
| Ad-Aware | Gen:Variant.Graftor.160428 |
| Agnitum | PUA.Toolbar.BitCocktail! |
| BitDefender | Gen:Variant.Graftor.160428 |
| DrWeb | Adware.Shopper.816 |
| ESET-NOD32 | a variant of Win64/Toolbar.Perion.B, a variant of Win32/Toolbar.BitCocktail.C, a variant of Win32/Toolbar.Perion.J |
| Emsisoft | Gen:Variant.Graftor.160428 (B) |
| F-Secure | Gen:Variant.Graftor.160428 |
| Fortinet | Adware/Perion |
| GData | Gen:Variant.Graftor.160428 |
| Ikarus | Win32.SuspectCrc |
| Malwarebytes | PUP.Optional.Pitaya |
| McAfee | Artemis!95751FBBE213, Artemis!D1D6CD981A71 |
| McAfee-GW-Edition | BehavesLike.Win32.CryptDoma.dm, BehavesLike.Win32.BadFile.gh |
| MicroWorld-eScan | Gen:Variant.Graftor.160428 |
| Symantec | WS.Reputation.1 |
| TrendMicro-HouseCall | Suspicious_GEN.F47V1129, Suspicious_GEN.F47V1119, TROJ_GEN.R08NH09K914 |
| VIPRE | Trojan.Win32.Generic!BT |
The detection percentage is based on that I've collected 275 scan results for the Acai Tech Ltd files. 28 of these scan reports came up with some sort of detection. If you like, you can review the full details of the scan reports by examining the files listed above.
The analysis is done on certificates with the following serial numbers: