Sophos detect Mal/JSRedir-AE with Internet Explorer 11 (11.63.10586.0 update 11.0.26) and no Malware with Google chrome

Question

While browsing the web, Sophos web control bock some website if we use IE 11 with the information : Malicious Content Blocked Mal/JSRedir-AE. 
 Sophos didn't detect anything on the same website with Google Chrome. 
 Where is the real problem ? It is sophos and IE11 or the website ? 
 
 Our solution : 
 we had to restore an old backup...

QC · Answer

Hello Roger, 
 a work around for this issue ok, let's first agree on what the issue is. Please have a look at the analysis for Mal/JSRedir-AE . Guess you shouldn't take it lightly and I wouldn't recommend to work around it If you look at its Summary page you see "Please send us a sample " (not possible though if it's blocked by download scanning) and that it's a generic detection which suggests it could be harmless but shouldn't indiscriminately be regarded as safe. 
 @Eric and @Roger (and TWIMC) As to different results for different browsers: Web pages try to be "smart" and tune the page for "optimum user experience" depending on the browser. Thus different scripts, style sheets, and so on might be loaded for different browsers. Unlikely that a redirection is needed to serve important content only when viewed with IE, or? More likely that the (admittedly potential) exploit kit is crafted for IE. On of the possible payloads for these drive-by attacks is ransomware (the kind that encrypts your files). Ransomware is not delivered for every request though, it's deliberately served only for a small fraction to "protect" the actual source of the threat. From the user's POV kinda inverse lottery. You don't want to be the one which hits the sh*tpot. 
 So, please, don't think these detections are written just to annoy you 
 Christian