diff --git a/src/corelib/io/qurl.cpp b/src/corelib/io/qurl.cpp
index d206df7c6c4..1e1a992719b 100644
--- a/src/corelib/io/qurl.cpp
+++ b/src/corelib/io/qurl.cpp
@@ -2717,8 +2717,12 @@ QUrl QUrl::resolved(const QUrl &relative) const
     qt_normalizePathSegments(
             &t.d->path,
             isLocalFile() ? QDirPrivate::DefaultNormalization : QDirPrivate::RemotePath);
-    if (!t.d->hasAuthority())
-        fixupNonAuthorityPath(&t.d->path);
+    if (!t.d->hasAuthority()) {
+        if (t.d->isLocalFile() && t.d->path.startsWith(u'/'))
+            t.d->sectionIsPresent |= QUrlPrivate::Host;
+        else
+            fixupNonAuthorityPath(&t.d->path);
+    }
 
 #if defined(QURL_DEBUG)
     qDebug("QUrl(\"%ls\").resolved(\"%ls\") = \"%ls\"",
@@ -2893,6 +2897,11 @@ QUrl QUrl::adjusted(QUrl::FormattingOptions options) const
         d->appendPath(path, options | FullyEncoded, QUrlPrivate::Path);
         that.d->setPath(path, 0, path.size());
     }
+    if (that.d->isLocalFile() && that.d->path.startsWith(u'/')) {
+        // ensure absolute file URLs have an empty authority to comply with the
+        // XDG file spec (note this may undo a RemoveAuthority)
+        that.d->sectionIsPresent |= QUrlPrivate::Host;
+    }
     return that;
 }
 
@@ -3307,15 +3316,18 @@ static QString fromNativeSeparators(const QString &pathName)
 QUrl QUrl::fromLocalFile(const QString &localFile)
 {
     QUrl url;
-    if (localFile.isEmpty())
+    QString deslashified = fromNativeSeparators(localFile);
+    if (deslashified.isEmpty())
         return url;
     QString scheme = fileScheme();
-    QString deslashified = fromNativeSeparators(localFile);
+    char16_t firstChar = deslashified.at(0).unicode();
+    char16_t secondChar = deslashified.size() > 1 ? deslashified.at(1).unicode() : u'\0';
 
     // magic for drives on windows
-    if (deslashified.size() > 1 && deslashified.at(1) == u':' && deslashified.at(0) != u'/') {
+    if (firstChar != u'/' && secondChar == u':') {
         deslashified.prepend(u'/');
-    } else if (deslashified.startsWith("//"_L1)) {
+        firstChar = u'/';
+    } else if (firstChar == u'/' && secondChar == u'/') {
         // magic for shared drive on windows
         qsizetype indexOfPath = deslashified.indexOf(u'/', 2);
         QStringView hostSpec = QStringView{deslashified}.mid(2, indexOfPath - 2);
@@ -3339,9 +3351,15 @@ QUrl QUrl::fromLocalFile(const QString &localFile)
             deslashified.clear();
         }
     }
+    if (firstChar == u'/') {
+        // ensure absolute file URLs have an empty authority to comply with the XDG file spec
+        url.detach();
+        url.d->sectionIsPresent |= QUrlPrivate::Host;
+    }
 
     url.setScheme(scheme);
     url.setPath(deslashified, DecodedMode);
+
     return url;
 }
 
diff --git a/tests/auto/corelib/io/qurl/tst_qurl.cpp b/tests/auto/corelib/io/qurl/tst_qurl.cpp
index 79c225ba64a..d47dfa2b08a 100644
--- a/tests/auto/corelib/io/qurl/tst_qurl.cpp
+++ b/tests/auto/corelib/io/qurl/tst_qurl.cpp
@@ -1500,10 +1500,13 @@ void tst_QUrl::fromLocalFileNormalize_data()
     QTest::newRow("relative-dot") << QString::fromLatin1("./a.txt") << QString::fromLatin1("file:./a.txt") << QString::fromLatin1("file:a.txt");
     QTest::newRow("relative-dot-dot") << QString::fromLatin1("././a.txt") << QString::fromLatin1("file:././a.txt") << QString::fromLatin1("file:a.txt");
     QTest::newRow("relative-path-dotdot") << QString::fromLatin1("b/../a.txt") << QString::fromLatin1("file:b/../a.txt") << QString::fromLatin1("file:a.txt");
+    QTest::newRow("relative-path-dotdot-dotdot") << QString::fromLatin1("b/../../a.txt") << QString::fromLatin1("file:b/../../a.txt") << QString::fromLatin1("file:../a.txt");
     QTest::newRow("absolute-path-dotdot") << QString::fromLatin1("/b/../a.txt") << QString::fromLatin1("file:///b/../a.txt") << QString::fromLatin1("file:///a.txt");
+    QTest::newRow("absolute-path-dotdot-dotdot") << QString::fromLatin1("/b/../../a.txt") << QString::fromLatin1("file:///b/../../a.txt") << QString::fromLatin1("file:///../a.txt");
     QTest::newRow("absolute-path-slash") << QString::fromLatin1("/b/") << QString::fromLatin1("file:///b/") << QString::fromLatin1("file:///b/");
     QTest::newRow("absolute-path-slahs-dot") << QString::fromLatin1("/b/.") << QString::fromLatin1("file:///b/.") << QString::fromLatin1("file:///b/");
     QTest::newRow("absolute-path-slahs-dot-slash") << QString::fromLatin1("/b/./") << QString::fromLatin1("file:///b/./") << QString::fromLatin1("file:///b/");
+    QTest::newRow("absolute-path-dotdot-slashslash") << QString::fromLatin1("/b/..//") << QString::fromLatin1("file:///b/..//") << QString::fromLatin1("file:////");
 }
 
 void tst_QUrl::fromLocalFileNormalize()