| Server IP : 202.155.9.250 / Your IP : 216.73.217.178 Web Server : LiteSpeed System : Linux srv339029361 5.15.0-177-generic #187-Ubuntu SMP Sat Apr 11 22:54:33 UTC 2026 x86_64 User : bigas1846 ( 1044) PHP Version : 8.0.30 Disable Function : pcntl_alarm,pcntl_fork,pcntl_waitpid,pcntl_wait,pcntl_wifexited,pcntl_wifstopped,pcntl_wifsignaled,pcntl_wifcontinued,pcntl_wexitstatus,pcntl_wtermsig,pcntl_wstopsig,pcntl_signal,pcntl_signal_get_handler,pcntl_signal_dispatch,pcntl_get_last_error,pcntl_strerror,pcntl_sigprocmask,pcntl_sigwaitinfo,pcntl_sigtimedwait,pcntl_exec,pcntl_getpriority,pcntl_setpriority,pcntl_async_signals,pcntl_unshare, MySQL : OFF | cURL : ON | WGET : ON | Perl : ON | Python : OFF | Sudo : ON | Pkexec : ON Directory : /usr/local/lsws/docs/ |
Upload File : |
<!DOCTYPE html>
<html lang="en-US">
<head>
<meta charset="utf-8" />
<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1" />
<title>OpenLiteSpeed Users' Manual - Security</title>
<meta name="description" content="OpenLiteSpeed Users' Manual - Security." />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<meta name="robots" content="noindex">
<script>
(function () {
var theme = 'light';
var resolved = false;
try {
if (window.localStorage) {
var storedTheme = window.localStorage.getItem('hdoc.theme');
if (storedTheme === 'light' || storedTheme === 'dark') {
theme = storedTheme;
resolved = true;
}
}
} catch (err) {
}
if (!resolved && window.matchMedia && window.matchMedia('(prefers-color-scheme: dark)').matches) {
theme = 'dark';
}
document.documentElement.setAttribute('data-theme', theme);
document.documentElement.style.colorScheme = theme;
}());
</script>
<link rel="shortcut icon" href="img/favicon.ico" />
<link rel="stylesheet" type="text/css" href="css/hdoc.css">
<link rel="stylesheet" type="text/css" href="css/hdoc-product-accent.css">
<script src="hdoc-search-index.js" defer></script>
<script src="js/hdoc-search.js" defer></script>
</head>
<body>
<div class="doc-shell">
<header class="doc-topbar">
<a class="doc-brand" href="index.html" aria-label="OpenLiteSpeed Users' Manual">
<img src="img/ols_logo.svg" alt="OpenLiteSpeed logo" />
<strong>OpenLiteSpeed Users' Manual</strong>
</a>
<div class="doc-actions">
<button class="doc-menu-toggle" type="button" aria-label="Open menu" data-menu-toggle aria-expanded="false">
<svg viewBox="0 0 24 24" aria-hidden="true" focusable="false"><path d="M3 12h18M3 6h18M3 18h18" stroke="currentColor" stroke-width="2" stroke-linecap="round"/></svg>
</button>
<form class="doc-search" role="search" data-empty="Search pages and settings" data-no-results="No results found.">
<label class="sr-only" for="doc-search-input">Search the manual</label>
<div class="doc-search__box">
<input id="doc-search-input" type="search" autocomplete="off" placeholder="Search pages and settings" aria-controls="doc-search-results" />
<button type="submit">Search</button>
</div>
<div id="doc-search-results" class="doc-search__results" hidden></div>
</form>
</div>
<label class="doc-language"><select id="doc-language-switcher" name="doc_language" data-language-switcher aria-label="Language"><option value="security.html" data-lang="en-US" selected>English</option><option value="es-ES/security.html" data-lang="es-ES">Español</option><option value="de-DE/security.html" data-lang="de-DE">Deutsch</option><option value="fr-FR/security.html" data-lang="fr-FR">Français</option><option value="zh-CN/security.html" data-lang="zh-CN">简体中文</option><option value="ja-JP/security.html" data-lang="ja-JP">日本語</option></select></label>
<button class="doc-theme-toggle" type="button" aria-label="Toggle theme" data-theme-toggle data-theme-light-label="Light mode" data-theme-dark-label="Dark mode" title="Toggle theme">
<span class="doc-theme-toggle__icon" aria-hidden="true"></span>
</button>
</header>
<div class="doc-menu-backdrop" data-menu-backdrop></div>
<div class="pagewrapper" data-current-lang="en-US" data-supported-langs="["en-US","es-ES","de-DE","fr-FR","zh-CN","ja-JP"]"><aside class="sidetree"><div class="sidetree__masthead"><figure class="sidetree__figure"><img src="img/ols_logo.svg" alt="OpenLiteSpeed logo" /></figure><div class="sidetree__identity"><a class="sidetree__manual-link" href="index.html">Users' Manual</a><div class="sidetree__version">Version 1.9 — Rev. 4</div></div></div><nav class="sidetree__nav" aria-label="Table of Contents"><ul class="sidetree__list">
<li><a href="license.html">License</a></li>
<li><a href="intro.html">Introduction</a></li>
<li><a href="install.html">Installation/Uninstallation</a></li>
<li>
<a href="admin.html">Administration</a>
<ul class="level2">
<li><a href="ServerStat_Help.html">Service Manager</a></li>
<li><a href="Real_Time_Stats_Help.html">Real-Time Stats</a></li>
</ul>
</li>
<li><a class="current" href="security.html">Security</a></li>
<li>
<a href="config.html">Configuration</a>
<ul class="level2">
<li><a href="ServGeneral_Help.html">Server General</a></li>
<li><a href="ServLog_Help.html">Server Log</a></li>
<li><a href="ServTuning_Help.html">Server Tuning</a></li>
<li><a href="ServSecurity_Help.html">Server Security</a></li>
<li>
<a href="ExtApp_Help.html">External Apps</a>
<ul class="level3">
<li><a href="External_LSAPI.html">LSAPI App</a></li>
<li><a href="External_WS.html">Web Server (Proxy)</a></li>
<li><a href="External_FCGI.html">Fast CGI App</a></li>
<li><a href="External_FCGI_Auth.html">Fast CGI Authorizer</a></li>
<li><a href="External_SCGI.html">Simple CGI App</a></li>
<li><a href="External_Servlet.html">Servlet Engine</a></li>
<li><a href="External_PL.html">Piped Logger</a></li>
<li><a href="External_LB.html">Load Balancer</a></li>
<li><a href="External_UWSGI.html">uWSGI</a></li>
</ul>
</li>
<li><a href="ScriptHandler_Help.html">Script Handler</a></li>
<li><a href="App_Server_Help.html">App Server Settings</a></li>
<li><a href="Module_Help.html">Module Configuration</a></li>
<li><a href="Listeners_General_Help.html">Listener General</a></li>
<li><a href="Listeners_SSL_Help.html">Listener SSL</a></li>
<li><a href="Templates_Help.html">Virtual Host Templates</a></li>
<li><a href="VirtualHosts_Help.html">Virtual Host Registration</a></li>
<li><a href="VHGeneral_Help.html">Virtual Host General</a></li>
<li><a href="VHSecurity_Help.html">Virtual Host Security</a></li>
<li><a href="VHSSL_Help.html">Virtual Host SSL</a></li>
<li><a href="Rewrite_Help.html">Rewrite</a></li>
<li>
<a href="Context_Help.html">Context</a>
<ul class="level3">
<li><a href="Static_Context.html">Static Context</a></li>
<li><a href="Java_Web_App_Context.html">Java Web App Context</a></li>
<li><a href="Servlet_Context.html">Servlet Context</a></li>
<li><a href="FCGI_Context.html">Fast CGI Context</a></li>
<li><a href="SCGI_Context.html">Simple CGI Context</a></li>
<li><a href="LSAPI_Context.html">LSAPI Context</a></li>
<li><a href="Proxy_Context.html">Proxy Context</a></li>
<li><a href="CGI_Context.html">CGI Context</a></li>
<li><a href="LB_Context.html">Load Balancer Context</a></li>
<li><a href="Redirect_Context.html">Redirect Context</a></li>
<li><a href="App_Server_Context.html">App Server Context</a></li>
<li><a href="UWSGI_Context.html">uWSGI Context</a></li>
<li><a href="Module_Context.html">Module Handler Context</a></li>
</ul>
</li>
<li><a href="VHWebSocket_Help.html">Web Socket Proxy</a></li>
</ul>
</li>
<li><a href="webconsole.html">Web Console</a>
<ul class="level2">
<li><a href="AdminGeneral_Help.html">Admin Console General</a></li>
<li><a href="AdminSecurity_Help.html">Admin Console Security</a></li>
<li><a href="AdminListeners_General_Help.html">Admin Listener General</a></li>
<li><a href="AdminListeners_SSL_Help.html">Admin Listener SSL</a></li>
</ul>
</li>
</ul></nav></aside><article class="contentwrapper"><div class="nav-bar"><div class="prev">« <a href="admin.html">Administration</a></div><div class="center"><a href="index.html">Home</a></div><div class="next"><a href="config.html">Configuration</a> »</div></div>
<h1>Security</h1><br/> <p>OpenLiteSpeed is designed with security as a top consideration. OLS supports SSL, has access control at server and virtual host levels, and context-specific realm protection. Besides these standard features, OLS also has the following special security features:</p><br/> <h2 id="connection-limits">Connection level limits</h2> <ul> <li>IP-level throttling limits network bandwidth to and from a single IP address regardless of the number of connections.</li> <li>IP-level connection accounting limits the number of concurrent connections from a single IP address. You can control this with the <strong>Connection Soft Limit</strong>, <strong>Connection Hard Limit</strong>, <strong>Grace Period</strong>, and <strong>Banned Period</strong> settings in the WebAdmin Console.</li> </ul><br/> <h2 id="request-checking">Request checking</h2> <p>Every HTTP request is vetted by OpenLiteSpeed. <span class="cmd">/.</span> is not allowed in a decoded URL, thus denying accessing hidden files and parent directories.</p> <p>Request size is limited by OpenLiteSpeed's <strong>Max Request URL Length</strong>, <strong>Max Request Header Length</strong> and <strong>Max Request Body Length</strong> settings.</p><br/> <h2 id="static-file-checking">Static file checking</h2> <p>OpenLiteSpeed will serve a static file only if the following conditions are satisfied:</p> <ul> <li>The file is readable by everyone.</li> <li>The file is not executable.</li> <li>The file is not in the access denied directory list.</li> <li>The file does not contain symbolic link if symbolic links are not allowed.</li> <li>By default, OpenLiteSpeed does not index a directory by listing its files, it has to be enabled explicitly.</li> </ul><br/> <h2 id="ext-app-firewall">External application firewall</h2> <p>OpenLiteSpeed forwards requests to external applications to process/generate dynamic content. Those applications can use a lot of system resources. The performance of the whole system will be severely degraded when system resource consumption reaches a certain point — when swapping space has to be used, for example. One way to conduct a DoS attack is to flood the web server with concurrent requests to a cumbersome external application.</p> <p>OpenLiteSpeed can pipeline requests and control the number of concurrent external application requests to prevent overconsumption of system resources. OLS caches requests and only forwards completed requests to the external application. This means the external application will not be held waiting while the server is receiving the request. OLS also caches the external application's response so that the external application can be released as soon as the response is completed and does not have to wait for the client to receive the complete response. This way the server can utilize fewer external application instances to serve more concurrent requests and achieve higher performance and scalability. OpenLiteSpeed also uses its own virtual memory to cache the request and response body to minimize the usage of system memory without sacrificing performance.</p><br/> <h2 id="cgi-resources">CGI resources consumption limit</h2> <p>OpenLiteSpeed restricts the amount of system resources that can be consumed by CGI applications. For each request to a CGI script, the web server needs to start a standalone CGI process to handle it. On a Unix system, the number of concurrent processes is limited. With the CGI resources consumption limit, you can configure the maximum number of concurrent CGI instances that the web server can launch. Excessive concurrent processes will degrade the performance of the whole system. (CGI processes are a common weapon for DoS attacks.) A system process limit can be specified per user in order to control the number of processes that can be spawned by a CGI application. Each process is further confined by CPU and memory limits.</p><br/> <h2 id="suexec">Enhanced CGI/FastCGI security with suEXEC</h2> <p>In order to reduce the security risks of a CGI or FastCGI script, OpenLiteSpeed can restrict the system resources the CGI script can access by running it in suEXEC mode. suEXEC starts the CGI or FastCGI script with a different user ID from that of the web server. This greatly improves security in a shared hosting environment by preventing one user's CGI script from accessing other users' files.</p> </article></div><button class="doc-back-to-top" type="button" aria-label="Back to top" data-back-to-top><svg viewBox="0 0 24 24" aria-hidden="true" focusable="false"><path d="M12 19V5" /><path d="m6 11 6-6 6 6" /></svg><span class="sr-only">Back to top</span></button><footer class="copyright">Copyright © 2013-2026. <a href="https://www.litespeedtech.com">LiteSpeed Technologies Inc.</a> All rights reserved.</footer>
</div>
</body>
</html>