diff --git a/admin/login.php b/admin/login.php
index 3c49bd36..e51d5789 100644
--- a/admin/login.php
+++ b/admin/login.php
@@ -4,7 +4,7 @@ include 'common.php';
 if ($user->hasLogin()) {
     $response->redirect($options->adminUrl);
 }
-$rememberName = htmlspecialchars(\Typecho\Cookie::get('__typecho_remember_name'));
+$rememberName = htmlspecialchars(\Typecho\Cookie::get('__typecho_remember_name', ''));
 \Typecho\Cookie::delete('__typecho_remember_name');
 
 $bodyClass = 'body-100';
@@ -25,7 +25,7 @@ include 'header.php';
             </p>
             <p class="submit">
                 <button type="submit" class="btn btn-l w-100 primary"><?php _e('登录'); ?></button>
-                <input type="hidden" name="referer" value="<?php echo htmlspecialchars($request->get('referer')); ?>" />
+                <input type="hidden" name="referer" value="<?php echo htmlspecialchars($request->get('referer') ?? ''); ?>" />
             </p>
             <p>
                 <label for="remember">
diff --git a/admin/manage-comments.php b/admin/manage-comments.php
index b97d20e3..b8ede5f3 100644
--- a/admin/manage-comments.php
+++ b/admin/manage-comments.php
@@ -69,7 +69,7 @@ $isAllComments = ('on' == $request->get('__typecho_all_comments') || 'on' == \Ty
                             (isset($request->status) ? 'status=' . htmlspecialchars($request->get('status')) : '') .
                             (isset($request->cid) ? (isset($request->status) ? '&' : '') . 'cid=' . htmlspecialchars($request->get('cid')) : '') : '')); ?>"><?php _e('&laquo; 取消筛选'); ?></a>
                             <?php endif; ?>
-                            <input type="text" class="text-s" placeholder="<?php _e('请输入关键字'); ?>" value="<?php echo htmlspecialchars($request->keywords); ?>"<?php if ('' == $request->keywords): ?> onclick="value='';name='keywords';" <?php else: ?> name="keywords"<?php endif; ?>/>
+                            <input type="text" class="text-s" placeholder="<?php _e('请输入关键字'); ?>" value="<?php echo htmlspecialchars($request->keywords ?? ''); ?>"<?php if ('' == $request->keywords): ?> onclick="value='';name='keywords';" <?php else: ?> name="keywords"<?php endif; ?>/>
                             <?php if(isset($request->status)): ?>
                                 <input type="hidden" value="<?php echo htmlspecialchars($request->get('status')); ?>" name="status" />
                             <?php endif; ?>
diff --git a/admin/manage-medias.php b/admin/manage-medias.php
index 7f41136c..3814f1bf 100644
--- a/admin/manage-medias.php
+++ b/admin/manage-medias.php
@@ -36,7 +36,7 @@ $attachments = \Widget\Contents\Attachment\Admin::alloc();
                                 <a href="<?php $options->adminUrl('manage-medias.php'); ?>"><?php _e('&laquo; 取消筛选'); ?></a>
                             <?php endif; ?>
                             <input type="text" class="text-s" placeholder="<?php _e('请输入关键字'); ?>"
-                                   value="<?php echo htmlspecialchars($request->keywords); ?>"<?php if ('' == $request->keywords): ?> onclick="value='';name='keywords';" <?php else: ?> name="keywords"<?php endif; ?>/>
+                                   value="<?php echo htmlspecialchars($request->keywords ?? ''); ?>"<?php if ('' == $request->keywords): ?> onclick="value='';name='keywords';" <?php else: ?> name="keywords"<?php endif; ?>/>
                             <button type="submit" class="btn btn-s"><?php _e('筛选'); ?></button>
                         </div>
                     </form>
diff --git a/admin/manage-pages.php b/admin/manage-pages.php
index 897a7e7d..d5150765 100644
--- a/admin/manage-pages.php
+++ b/admin/manage-pages.php
@@ -39,7 +39,7 @@ $pages = \Widget\Contents\Page\Admin::alloc();
                                 <a href="<?php $options->adminUrl('manage-pages.php'); ?>"><?php _e('&laquo; 取消筛选'); ?></a>
                             <?php endif; ?>
                             <input type="text" class="text-s" placeholder="<?php _e('请输入关键字'); ?>"
-                                   value="<?php echo htmlspecialchars($request->keywords); ?>" name="keywords"/>
+                                   value="<?php echo htmlspecialchars($request->keywords ?? ''); ?>" name="keywords"/>
                             <button type="submit" class="btn btn-s"><?php _e('筛选'); ?></button>
                         </div>
                     </form>
diff --git a/admin/manage-users.php b/admin/manage-users.php
index 025efe24..c4b8186b 100644
--- a/admin/manage-users.php
+++ b/admin/manage-users.php
@@ -31,7 +31,7 @@ $users = \Widget\Users\Admin::alloc();
                                 <a href="<?php $options->adminUrl('manage-users.php'); ?>"><?php _e('&laquo; 取消筛选'); ?></a>
                             <?php endif; ?>
                             <input type="text" class="text-s" placeholder="<?php _e('请输入关键字'); ?>"
-                                   value="<?php echo htmlspecialchars($request->keywords); ?>" name="keywords"/>
+                                   value="<?php echo htmlspecialchars($request->keywords ?? ''); ?>" name="keywords"/>
                             <button type="submit" class="btn btn-s"><?php _e('筛选'); ?></button>
                         </div>
                     </form>
diff --git a/admin/write-page.php b/admin/write-page.php
index 25c4820a..4ab81db7 100644
--- a/admin/write-page.php
+++ b/admin/write-page.php
@@ -34,7 +34,7 @@ include 'menu.php';
                     if ($page->have()) {
                         $permalink = str_replace('{cid}', $page->cid, $permalink);
                     }
-                    $input = '<input type="text" id="slug" name="slug" autocomplete="off" value="' . htmlspecialchars($page->slug) . '" class="mono" />';
+                    $input = '<input type="text" id="slug" name="slug" autocomplete="off" value="' . htmlspecialchars($page->slug ?? '') . '" class="mono" />';
                     ?>
                     <p class="mono url-slug">
                         <label for="slug" class="sr-only"><?php _e('网址缩略名'); ?></label>
@@ -43,7 +43,7 @@ include 'menu.php';
                     <p>
                         <label for="text" class="sr-only"><?php _e('页面内容'); ?></label>
                         <textarea style="height: <?php $options->editorSize(); ?>px" autocomplete="off" id="text"
-                                  name="text" class="w-100 mono"><?php echo htmlspecialchars($page->text); ?></textarea>
+                                  name="text" class="w-100 mono"><?php echo htmlspecialchars($page->text ?? ''); ?></textarea>
                     </p>
 
                     <?php include 'custom-fields.php'; ?>
diff --git a/admin/write-post.php b/admin/write-post.php
index 896b4b00..1f9a40a8 100644
--- a/admin/write-post.php
+++ b/admin/write-post.php
@@ -38,7 +38,7 @@ include 'menu.php';
                             $post->cid, $post->category, $post->year, $post->month, $post->day
                         ], $permalink);
                     }
-                    $input = '<input type="text" id="slug" name="slug" autocomplete="off" value="' . htmlspecialchars($post->slug) . '" class="mono" />';
+                    $input = '<input type="text" id="slug" name="slug" autocomplete="off" value="' . htmlspecialchars($post->slug ?? '') . '" class="mono" />';
                     ?>
                     <p class="mono url-slug">
                         <label for="slug" class="sr-only"><?php _e('网址缩略名'); ?></label>
@@ -47,7 +47,7 @@ include 'menu.php';
                     <p>
                         <label for="text" class="sr-only"><?php _e('文章内容'); ?></label>
                         <textarea style="height: <?php $options->editorSize(); ?>px" autocomplete="off" id="text"
-                                  name="text" class="w-100 mono"><?php echo htmlspecialchars($post->text); ?></textarea>
+                                  name="text" class="w-100 mono"><?php echo htmlspecialchars($post->text ?? ''); ?></textarea>
                     </p>
 
                     <?php include 'custom-fields.php'; ?>
@@ -134,7 +134,7 @@ include 'menu.php';
                                                 <option
                                                     value="hidden"<?php if ($post->status == 'hidden'): ?> selected<?php endif; ?>><?php _e('隐藏'); ?></option>
                                                 <option
-                                                    value="password"<?php if (strlen($post->password) > 0): ?> selected<?php endif; ?>><?php _e('密码保护'); ?></option>
+                                                    value="password"<?php if (strlen($post->password ?? '') > 0): ?> selected<?php endif; ?>><?php _e('密码保护'); ?></option>
                                                 <option
                                                     value="private"<?php if ($post->status == 'private'): ?> selected<?php endif; ?>><?php _e('私密'); ?></option>
                                             <?php endif; ?>
@@ -142,7 +142,7 @@ include 'menu.php';
                                                 value="waiting"<?php if (!$user->pass('editor', true) || $post->status == 'waiting'): ?> selected<?php endif; ?>><?php _e('待审核'); ?></option>
                                         </select>
                                     </p>
-                                    <p id="post-password"<?php if (strlen($post->password) == 0): ?> class="hidden"<?php endif; ?>>
+                                    <p id="post-password"<?php if (strlen($post->password ?? '') == 0): ?> class="hidden"<?php endif; ?>>
                                         <label for="protect-pwd" class="sr-only">内容密码</label>
                                         <input type="text" name="password" id="protect-pwd" class="text-s"
                                                value="<?php $post->password(); ?>" size="16"
diff --git a/var/Typecho/Response.php b/var/Typecho/Response.php
index 57f19fae..fa11d565 100644
--- a/var/Typecho/Response.php
+++ b/var/Typecho/Response.php
@@ -209,7 +209,7 @@ class Response
                 $timeout = 1;
             }
 
-            setrawcookie($key, rawurlencode($value), $timeout, $path, $domain);
+            setrawcookie($key, rawurlencode($value), $timeout, $path, $domain ?? '');
         }
     }
 
diff --git a/var/Widget/Archive.php b/var/Widget/Archive.php
index 621f83ba..1bd3b5ea 100644
--- a/var/Widget/Archive.php
+++ b/var/Widget/Archive.php
@@ -1289,7 +1289,7 @@ class Archive extends Contents
         if ($return) {
             return $value;
         } else {
-            echo htmlspecialchars($value);
+            echo htmlspecialchars($value ?? '');
         }
     }
 
diff --git a/var/Widget/User.php b/var/Widget/User.php
index 94dc9231..700bf1ad 100644
--- a/var/Widget/User.php
+++ b/var/Widget/User.php
@@ -268,7 +268,7 @@ class User extends Users
             } else {
                 //防止循环重定向
                 $this->response->redirect(defined('__TYPECHO_ADMIN__') ? $this->options->loginUrl .
-                    (0 === strpos($this->request->getReferer(), $this->options->loginUrl) ? '' :
+                    (0 === strpos($this->request->getReferer() ?? '', $this->options->loginUrl) ? '' :
                         '?referer=' . urlencode($this->request->makeUriByRequest())) : $this->options->siteUrl, false);
             }
         }