Here is one example of an album cover that gets blocked when you visit musicbrainz.org, note that the frontpage rotates between newly added covers.
hxxps://ia801509.us.archive.org/29/items/mbid-c7a94cae-f2e7-45cb-a91e-299135f04e70/mbid-c7a94cae-f2e7-45cb-a91e-299135f04e70-18245668240_thumb250.jpg
This has to be a false positive, archive.org hosts lots of album art for that site. Lots of the other images on that site still works, it just seems to be that subdomain.
Here is the log:
Malwarebytes
www.malwarebytes.com
-Log Details-
Protection Event Date: 11/6/17
Protection Event Time: 5:53 PM
Log File: 0dae7bf4-c313-11e7-96a7-086266c88b25.json
Administrator: Yes
-Software Information-
Version: 3.3.1.2183
Components Version: 1.0.236
Update Package Version: 1.0.3189
License: Premium
-System Information-
OS: Windows 10 (Build 16299.19)
CPU: x64
File System: NTFS
User: System
-Blocked Website Details-
Malicious Website: 1
, , Blocked, [-1], [-1],0.0.0
-Website Data-
Domain: ia801509.us.archive.org
IP Address: 207.241.228.159
Port: [53747]
Type: Outbound
File: C:\Program Files\Mozilla Firefox\firefox.exe