How to block user agent. Here is the filtering rule I a.
How to block user agent Identifying User Agent Strings. SecFilterSelective HTTP_USER_AGENT "Agent Name 1" SecFilterSelective HTTP_USER_AGENT "Agent Name 2" SecFilterSelective HTTP_USER_AGENT "Agent Name 3" Also we can block them using htaccess or robots. htaccess. For example, if a user’s product were called Apr 27, 2023 · Within Device Platform condition Azure AD identifies the platform by using information provided by the device, such as user agent strings. Block access based on: User-agent Header Block request that: Matches the Pattern Pattern (User-agent Header): *Googlebot* Using: Wildcards How to block: Abort Request Click OK when complete. 0 Learn how to configure the Apache server to deny access to your website based on the USER-AGENT value. htaccess file: Jan 8, 2024 · Implementation Steps for Blocking User Agents or Bots 1. Jan 28, 2023 · User agents can be easily faked by malicious actors in order to bypass security measures that are in place to block certain types of user agents. Conditional Access policies using this condition should be used with another policy, like one requiring device compliance or app protection policies, to mitigate the risk of user agent spoofing. The traditional use case for a user agent is to detect browser types so the server can return an optimized page. htaccess file: Deny from "User-Agent: <user-agent-string>" Replace <user-agent-string> with the actual user agent string you want to block. User Agents. If traffic from some non-browser user agents is being erroneously blocked, you can create an exception by setting the offending AWS WAF Bot Control rule SignalNonBrowserUserAgent to Count and then combining the rule's labeling with your exception criteria. You can do the same with Googlebot using “User-agent: Googlebot”. Jun 27, 2012 · Question, is how to block a block that spoofs its user-agent, where it’s clear that the user agent is spoofed by the Comments token. Apr 1, 2021 · RewriteEngine On RewriteCond %{HTTP_USER_AGENT} spamcrawler [NC,OR] RewriteCond %{HTTP_USER_AGENT} spambot [NC,OR] RewriteRule . conf file. Other than that, you may have to use scripts (php, ruby, python) for this. Apr 5, 2024 · You can then type Go-http-client*, give a brief Block Reason and hit the blue “BLOCK VISITORS MATCHING THIS PATTERN” button to save changes. Mar 8, 2017 · You have to use the . In Action, select the action to perform: Managed Challenge, Block, JS Challenge, or Interactive Challenge. You can use the following key commands to build the iRule: The [HTTP::header "User-Agent"] command returns the user-agent string from the client-request header. htaccess block bot like Googlebot, you would use: Deny from "User-Agent: Googlebot/2. You can add any specific file type(s) to block in Applies To, or you can leave it blank to make it apply to all file types. Blocking IP addresses, User Agents or Referres may cause unforseen issues, since it’s easy to block more then expected. How can I do this to: Chrome, Safari, Firefox, Opera, My WebOS 7. For example, to . So SetEnvIf would be more appropriate most of the time. Jul 14, 2020 · Description Use ASM to block request with custom user agent Also have such requests is that in the ASM application event logs for visibility as well as determination of which requests are generating violations Environment ASM User-agents iRule Event logs Cause By default, ASM does not inspect user-agent and requires user-defined violations Recommended Actions Create an application security Jul 21, 2011 · Hi! I would like to block Custom user agents in Ironport Web Security without blocking IE. Since user agent strings can be modified, this information is unverified. Begin by identifying the user agent strings associated with the bots or user agents you want to block. eg. Block access based on: User-agent Header; Block request that: Matches the Pattern; Pattern (User-agent Header): ^$ Using: Regular Expression; How to block: Abort Request; Rule will be the same as other replies given with the caveat that you don't seem to be able to rename it. This can be done by modifying the user agent string that is sent with HTTP requests to make it appear as if the request is coming from a different type of device or browser. Aug 29, 2017 · This article describes how to use FortiWeb advanced protection rules and policies to restrict access to web applications from certain browsers or block unknown browsers/user-agents. The standard for robot exclusion defines a file, /robots. Jul 9, 2011 · Is it possible to ban certain user agents directly from web. Keep in mind that user agent filtering is not foolproof and can be easily bypassed by users who know how to modify their user agent Mar 5, 2014 · Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising Reach devs & technologists worldwide about your product, service or employer brand Sep 21, 2020 · To configure user-agent block list, open the nginx configuration file of your website, where the server section is defined. * bad_bot User-Agent strings are often a specific case, so should be matched cased-sensitively. Select Using: regular expressions. * means any number of any characters). This article will go in-depth on how to block specific user agent(s) and referers on a NGINX or Apache web server. *(SCspider|Textbot|s2bot). txt, and to avoid pointless server load (and log-file spamming) I'd like to prevent certain classes of request (in particular based on user-agent or very perhaps IP-address) from proceeding. But the most part of crawling bots is not helpful, moreover, they harm the site performance. A “user agent” is a software agent that is acting on behalf of a user. *BingPreview. Here’s a simplified example of how to block a specific User-Agent: RewriteEngine On RewriteCond %{HTTP_USER_AGENT} harmfulbot [NC] RewriteRule Dec 12, 2018 · You can create an iRule to block requests containing certain elements. I've added a request filtering rule, but I know it is still hitting the site because it shows up in Google Analytics. For example, if you want to block a User Agent named Textbot, add it as: RewriteEngine On RewriteCond %{HTTP_USER_AGENT} Textbot [NC] RewriteRule . X Cause None. txt behavior is really dubious; its operator said if one don’t block it specifically (even if you block *ALL* other bots with `User-Agent: *`), it would try to invite itself in as if it was being “Googlebot” and scrape on anyway if the site happens to allow Googlebot (which I’d imagine many people’s site do). You need to block traffic from any user agent that does not contain “Edg” for only the /media/* path. For example: RewriteCond %{HTTP_USER_AGENT} "=This is the exact user-agent I want to block" RewriteRule ^ - [F] Dec 9, 2016 · The "problem" here is that there is actually no input style in the author stylesheet (see the spec for more info), and therefore the style that is defined in the user agent stylesheet is used. SetEnvIfNoCase User-Agent . In your case: ( Please put this in the very beginning of the . This pattern means any user agent string containing BingPreview (the ^ and $ indicate the start and end of the string, and . We receive a lot of requests regarding the addition of a specific user-agent to block bot requests by Imunify360 rules. Click on the rule and then click Rename on the right hand side, name the rule something appropriate for reference sake. And restarted apache to take effect: service apache2 restart Under User Agent Blocking, select Create blocking rule. We are getting lots of requests with no user agent set. Block a single bad User-Agent. What is a user-agent you might ask? Well, it is a string, which usually defines the browser and operating system of the device from which the request originated. g. named SCspider, Textbot, and s2bot), do that with the . config? Certain robots seem not to follow robots. In these events you can also block users by their User-Agent strings. If you see a User-Agent that contains "GoogleBot" then it's most certainly a bad bot. *$. The contains operator verifies whether the user-agent string contains the matching element. AI User-agent: meta-ai User-agent: metaai Disallow: / I then asked Meta AI if it could provide me with the source of this information, but none of the sources it provided mentioned anything about how to block Meta AI or what the Meta AI user agent is. I am able to configure a section within the security section in the WAF, where I can block bad bots, and any other bad user agent (e. May 29, 2014 · Select User-agent Header for the “block access based on” field. - [R=403,L] The first line above enables mod_rewrite, while the next two lines check the exact user-agent value of each request and block the ones with user-agent values as spambot or spamcrawler. I am now using cPanel and would like to block specific user agents from accessing any websites on my server. Unusual Behavior: Legitimate browsers and applications always send a user agent. Feb 10, 2021 · If you want to match an entire user-agent string then you can use the = (lexicographical string comparison for equality) prefix operator (together with double-quotes) on the CondPattern to test for an exact match. The format of the user-agent string in HTTP is a list of product tokens (keywords) with optional comments. By sending no user agent, malicious actors attempt to bypass such filters. Also note that this is a regex by default, so any special/meta regex characters also need to be escaped (that includes . Webmasters beware. 0) Oct 24, 2013 · I'm trying to block requests from a certain bot. If you end with a * , variants of the same User Agent going forward should also be blocked. Any example code? Jul 24, 2023 · On the other hand, a user agent is simply a software package with the responsibility of retrieving, rendering and interacting with end users’ web content. 0 Dec 12, 2018 · You can create an iRule to block requests containing certain elements. " It's a user agent commonly used by older email apps and devices that rely on basic authentication to access email accounts. Online Resources. Aug 23, 2023 · Its robots. 0 (compatible; MSIE 8. the following user-agent string: Blocking applications with custom signatures. python, Go lang, Java, etc) used by not authorised external users to scan the website for vulnerabilities, etc. htacces rules below: It checks the HTTP_USER_AGENT header of the incoming request to see if it matches the pattern ^. The activity of crawling bots and spider bots of well-known search engines usually does no matter site load and does not affect a website's work speed. c> RewriteEngine On RewriteCond %{HTTP_USER_AGENT} (EvilBotHere|SpamSpewer|SecretAgentAgent) [NC] RewriteRule (. txt by example but I want in php. txt that specifies those portions of your website where you wish to exclude robots. Mar 27, 2019 · By blocking their User Agents, you will stop any traffic that contains the specified name in the user agent field. * - [F,L] To block the requests from machines with missing User Agent, add the following rules in your . Here’s the basic syntax for blocking a specific user agent in your . 1. User agent: BAV2ROPC While host authenticating with legacy protocol, it will recognized as user agent. I tend to suspect a browser or some exploit as a potential cause, given the pace of the attack, IP variability, and network speed differences. If you are having multiple sites configured and want to block for a specific URL, then you may want to put them in respective VirtualHost section. config. Blocking of Robots Description: In this recipe, we discuss how to block persistent requests from a particular robot, or user agent. 1" Dec 12, 2023 · Use the ’RewriteCond’ directive to specify the User-Agents you wish to block. In the case of this question, you would put "Yandex" here. However, user agents are often misused by malware, and are used to communicate the identity of the client to the BotNet controller over Jun 6, 2019 · User-agent: Bingbot Disallow: / User-agent: * Disallow: This will block Bing’s search engine bot from crawling your site, but other bots will be allowed to crawl everything. Oct 21, 2015 · I used to manage all of my web servers manually via nginx. Nov 4, 2021 · You can easily block with . To block more than one User Agent (e. 0; Trident/4. 0; Windows NT 6. By clicking Accept, you agree to the storing of cookies on your device to enhance your community and translation experience. You can also block specific bots from accessing specific files and folders. Nov 5, 2021 · Some malicious users will send requests from different IP addresses, but still using the same User-Agent for sending all of the requests. There are many situations you may need to block the IP address of a user when running a WordPress blog. WAF1 protects a web app. Apr 4, 2014 · The BrowserMatchNoCase allows case insensitive matches against the user agent. Jan 13, 2015 · Hi All We have a requirement to restrict the user agent through palo alto firewall. If you just wanted to block one particular User-Agent string, you could use this RewriteRule: The full user agent is not required unless you match with ^$, so "Google" would work. Fortunately, it is possible to block those bots based on their user-agent string. Obviously, this can vary. Microsoft recognizes it as a legacy application. For example allow web-browsing only from internet - 12048 This website uses Cookies. < IfModule mod_rewrite. A lot of them are made publicly available. What are the legacy protocols Pop3 Imap Smtp auth Working of bav2ropc When the application tries to access your mailbox with basic authentication. htaccess file. htaccess file) RewriteEngine On RewriteCond %{HTTP_USER_AGENT} Tachiyomi [NC] RewriteRule . CondPattern - 2nd argument to the RewriteCond directive) in double quotes. Here is the filtering rule I a Oct 29, 2020 · I am seeing this same attack. The device platform condition is based on user agent strings. SetEnvIfNoCase Referer "^$" bad_user SetEnvIfNoCase User-Agent "python" bad_user SetEnvIfNoCase User-Agent "catexplorador" bad_user SetEnvIfNoCase User-Agent "^$" bad_user Order Deny,Allow Deny from env=bad_bot Apr 3, 2025 · Users are blocked from accessing company resources when the device type is unknown or unsupported. *) - [F,L] </IfModule> To add more bots, use a pipe (|) separator: Jan 19, 2016 · I am currently researching a way to be able to intercept traffic from an unsupported IE browser and then be able to feed that information about the host, mainly FQDN hostname or IP address of the host into the PAN dynamically based on the user-agent: IE8 - Mozilla/4. May 11, 2018 · You either need to backslash escape the spaces in the user-agent string, or enclose the entire user-agent (ie. I used the below pattern for my rule Apr 19, 2022 · How to Block User Agents and Referrer Sites . Traffic with an empty user agent is almost exclusively non-human. Feb 22, 2011 · Give it a name, and then in the Scan Headers section, put "User-Agent". * - [F,L] It is recommended to add them in the very beginning of the . Apr 9, 2024 · I mean, when I am managing Web Application Firewalls (WAF) from other provider. Combine it with ’RewriteRule’ to enforce the block, usually by sending a 403 Forbidden response. Mar 2, 2023 · Description To block a Web Crawler or similar not desired requests that contain the same User-Agent string in their HTTP header, you can use custom attack signatures. It's hard to scale a user-agent based rule in nginx alone: You can use regex to match a number of user agents in the if block. Solution In FortiWeb restrict browsers by: - Creating FortiWeb custom rules and policies to detect browsers based on http header 'User-Agent'. i. Jul 13, 2021 · You may notice that some bots often visit and scan your website aggressively, which wastes a lot of web server resources. htaccess file to block that this particular user agent: The htaccess content should be: RewriteEngine On SetEnvIfNoCase User-Agent "Mozilla/5. Issue. Dec 12, 2017 · I read the solution to block null/empty user-agent request here but I was checking if we can block it by web. Environment BIG-IP ASM 15. *) - [F,L] </ IfModule > REPLACE: Replace EXAMPLE_USER_AGENT with the bad user agent. If a bot repeatedly accesses your site under a specific user agent, block it with: # Block via User-Agent <IfModule mod_rewrite. Popular examples of user agents known to the Linux ecosystem include Curl and Wget . c > RewriteEngine On RewriteCond %{HTTP_USER_AGENT} EXAMPLE_USER_AGENT RewriteRule (. Jul 10, 2023 · One of the important aspects of securing your WordPress site is monitoring the IP addresses of users and user agents accessing your site. e. Mar 2, 2025 · Blocking via User-Agent. In Ban Users->Ban User Agents, what format do I enter? For exam… AI / LLM User-Agents: Blocking Guide Why Block AI/LLM User Agents? As AI, Large Language Models (LLMs) and AI Agents become more prevalent, website owners may want to control access to their content for several reasons:. Dec 3, 2024 · Avoidance of Detection: Many security systems use user agent strings to filter bots. Sep 1, 2009 · there have a way to block some of user agent via php script? Example on mod_security. You have an Azure subscription that contains a Web Application Firewall (WAF) named WAF1. Dec 23, 2024 · User-agent: MetaAI User-agent: Meta-AI User-agent: Meta AI User-agent: Meta. Custom signatures can be used in application control profiles to block web traffic from specific applications, such as out of support operating systems. Example Directive. *$ [NC] RewriteRule . These strings are often found in the HTTP request headers sent by browsers or bots. Then enter your pattern. * - [F,L] In above Tachiyomi is user agent name, if you have different name just replace it. The User Agent page lists common and uncommon user agents in HTTP communications. Ensure the module is enabled and then add the following in either . In Deny Strings, enter all of the user agent strings you want to block. Enter a user agent value in User Agent (wildcards such as * are not supported). htaccess file or respective . Blocking that browser string (as opposed to the IP's, which are all over the place) seems like the best call. It is possible to do a Google search, and there is also a very useful website that has a list of a lot of the common user agents. *abcbot. Enter a descriptive name for the rule in Name/Description. Jan 4, 2024 · Here's an explanation of the situation and steps to block the BAV2ROPC user agent: Understanding BAV2ROPC: BAV2ROPC stands for "Basic Authentication Version 2 Resource Owner Password Credential. The (relevant) user agent rule (on chrome) is: input, input[type="password"], input[type="search"] { cursor: auto; } How To Block Bots By User-agent Why you should block some crawling bots . There are lots of online resources available to find out the user agent. Below, you can find the detailed instructions on how to do it on a temporary basis (before rules update) and on a permanent basis. , (and )). Feb 10, 2025 · How to block User Agent Resolved baldguy (@baldguy) 2 months, 4 weeks ago I want to block some bots that are hitting my site hard. Nov 1, 2024 · To block user-agent in Apache, you can use the mod_rewrite module. A second option is to use the SetEnvIfNoCase command. htacces rules below: RewriteEngine On RewriteCond %{HTTP_USER_AGENT} ^. Mar 16, 2025 · Question. mrtqkaaijoktsucjyplapdrzqraksvldwzsodxqyzsoynhxfkurffb