diff --git a/CHANGELOG.md b/CHANGELOG.md
index 07f4f97..98c2df6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -77,6 +77,7 @@ For major (breaking) changes - **version 4, 3 and 2** - see end of page.
 
 | Version        | Date           | Comment  |
 | -------------- | -------------- | -------- |
+| 5.7.12         | 2021-07-27     | `osInfo()` fix uefi detection (win) |
 | 5.7.11         | 2021-07-27     | typescript typings fix `bluetoothDevices()` |
 | 5.7.10         | 2021-07-26     | typescript typings fix `processLoad()` |
 | 5.7.9          | 2021-07-25     | `uuid()` better regedit path detection (win) |
diff --git a/docs/history.html b/docs/history.html
index 1a955cf..bef06fa 100644
--- a/docs/history.html
+++ b/docs/history.html
@@ -56,6 +56,11 @@
                   </tr>
                 </thead>
                 <tbody>
+                  <tr>
+                    <th scope="row">5.7.12</th>
+                    <td>2021-07-27</td>
+                    <td><span class="code">osInfo()</span> fix uefi detection (win)</td>
+                  </tr>
                   <tr>
                     <th scope="row">5.7.11</th>
                     <td>2021-07-27</td>
diff --git a/docs/index.html b/docs/index.html
index 4971a68..a8e7d8d 100644
--- a/docs/index.html
+++ b/docs/index.html
@@ -170,7 +170,7 @@
       <img class="logo" src="assets/logo.png">
       <div class="title">systeminformation</div>
       <div class="subtitle"><span id="typed"></span>&nbsp;</div>
-      <div class="version">New Version: <span id="version">5.7.11</span></div>
+      <div class="version">New Version: <span id="version">5.7.12</span></div>
       <button class="btn btn-light" onclick="location.href='https://github.com/sebhildebrandt/systeminformation'">View on Github <i class=" fab fa-github"></i></button>
     </div>
     <div class="down">
diff --git a/lib/osinfo.js b/lib/osinfo.js
index 6d34630..685ef9b 100644
--- a/lib/osinfo.js
+++ b/lib/osinfo.js
@@ -365,14 +365,14 @@ function isUefiLinux() {
     process.nextTick(() => {
       fs.stat('/sys/firmware/efi', function (err) {
         if (!err) {
-          resolve(true);
+          return resolve(true);
         } else {
           exec('dmesg | grep -E "EFI v"', function (error, stdout) {
             if (!error) {
               const lines = stdout.toString().split('\n');
-              resolve(lines.length > 0);
+              return resolve(lines.length > 0);
             }
-            resolve(false);
+            return resolve(false);
           });
         }
       });
@@ -387,21 +387,20 @@ function isUefiWindows() {
         exec('findstr /C:"Detected boot environment" "%windir%\\Panther\\setupact.log"', util.execOptsWin, function (error, stdout) {
           if (!error) {
             const line = stdout.toString().split('\n\r')[0];
-            resolve(line.toLowerCase().indexOf('efi') >= 0);
-            return;
+            return resolve(line.toLowerCase().indexOf('efi') >= 0);
           } else {
             exec('echo %firmware_type%', util.execOptsWin, function (error, stdout) {
               if (!error) {
                 const line = stdout.toString() || '';
-                resolve(line.toLowerCase().indexOf('efi') >= 0);
+                return resolve(line.toLowerCase().indexOf('efi') >= 0);
               }
-              resolve(false);
+              return resolve(false);
             });
           }
-          resolve(false);
+          return resolve(false);
         });
       } catch (e) {
-        resolve(false);
+        return resolve(false);
       }
     });
   });
@@ -1015,18 +1014,18 @@ function shell(callback) {
     process.nextTick(() => {
       if (_windows) {
         resolve('cmd');
+      } else {
+        let result = '';
+        exec('echo $SHELL', function (error, stdout) {
+          if (!error) {
+            result = stdout.toString().split('\n')[0];
+          }
+          if (callback) {
+            callback(result);
+          }
+          resolve(result);
+        });
       }
-
-      let result = '';
-      exec('echo $SHELL', function (error, stdout) {
-        if (!error) {
-          result = stdout.toString().split('\n')[0];
-        }
-        if (callback) {
-          callback(result);
-        }
-        resolve(result);
-      });
     });
   });
 }