My Defender identified this virus—Trojan:JS/Cryxos.ASI!MTB—in the browser cache, and I don't know if it might have infected my machine.

Question

My Defender identified this virus—Trojan:JS/Cryxos.ASI!MTB—in the browser cache, and I don't know if it might have infected my machine.

User34518 0

I ran a full scan with Defender and found this virus; I clicked "remove," but now I don't know what else to do. I cleared my browser caches, but I'm not sure if that's enough. I ran the antivirus again and it reports zero threats, but I don't know if I can trust that or if the virus has infected my system. Captura de tela 2026-08-03 153520

0 comments

3 answers

Your answer

Answer 1

Paulo GM 70,625 Independent Advisor

Yes, your device should be safe now that the threat has been removed. This type of virus is generally not persistent, but as mentioned earlier, it's still important to avoid clicking suspicious links, especially those found on malicious websites or in unsolicited emails.

Since these threats can also be delivered through malicious ads, I recommend using an ad blocker to reduce the number of ads you encounter while browsing the web.

https://microsoftedge.microsoft.com/addons/detail/ublock-origin/odfafepnkmbhccpbejgmiehpchacaeak

0 comments

Answer 2

Paulo GM 70,625 Independent Advisor

Hi,

Aside from the information provided by the AI, this type of virus is often associated with deceptive desktop notifications, such as fake virus alerts. Since you've already removed it and the scan found zero threats, your device should be safe for now.

As an additional precaution, avoid clicking links from suspicious websites or emails, as they may lead to malicious content or trigger similar threats. If you're using Edge, I also recommend enabling the following security options under Settings > Privacy, search, and services > Security:

Protect from harmful sites and downloads
Enhance your security on the web

User34518 0 Reputation points

2026-08-07T18:52:14.5033333+00:00

So, is my device safe? Is this type of virus persistent? Can I trust Defender that it removed the threat and there are no viruses left, given that the other scans found nothing?

Thank you very much.

Answer 3

If Defender now shows Status: Removed and a new scan reports zero threats, that indicates the detected item was removed. In Protection history, Threat blocked means Defender blocked and removed the threat, and Threat quarantined means it was isolated and not currently a risk until removed. Since the detection was in the browser cache, clearing the cache was also an appropriate step.

To increase confidence that nothing persistent remains:

Open Windows Security > Virus & threat protection > Scan options.
Run a Full scan.
Then run Microsoft Defender Antivirus (offline scan). This restarts the PC and scans outside Windows, which helps detect malware that hides while Windows is running. Save open files first, because the device will restart.
After Windows starts again, open Windows Security and check Protection history for the offline scan results.

If the same malware is detected again after a restart, that can indicate a hidden component is reinstalling it. In that case, Microsoft recommends using Microsoft Defender Offline specifically for recurring malware.

If Defender reports Remediation incomplete or partially removed, follow the additional cleanup steps shown there. One supported next step is to run the Malicious Software Removal Tool:

Press Windows key + R.
Type %windir%\system32\mrt.exe and select OK.
If prompted, select Yes.
Follow the prompts to scan and clean the PC.
Restart the PC, then install the latest Windows updates.

If scans stay clean and no new detections appear after restart, that is consistent with the threat having been removed.