mod_sed is a stream filter module for Apache HTTPD web server. mod_sed is used for filtering requests before they are passed to a server program, typically a CGI program. This issue results in an attacker being able to send a specially crafted request which will cause the server to attempt to write data from the request's data stream into the server's heap memory, resulting in a crash of the server. This vulnerability can be exploited by attackers with low privileged user rights. This issue only affects installations that have mod_sed enabled. With mod_sed enabled, you can get an Out-of-bounds Write in mod_sed as follows. 1. On Debian/Raspbian, edit the /etc/apache2/mods-enabled/nologin.conf file and add a new line after the '#' character like below. IfModule mod_sed_module> Filter_ passes_as_doc_stream "A HREF=\"\" data for user-agent\">" Filter_pass_through "script>alert('XSS');/script>" /IfModule> This will allow you to put HTML code in the data stream. 2. Change to the /var/www/html/subdirectory/subdirectory/subdirectory/subdirectory/subdirectory/ subdirectory/subdirectory/subdirectory/subdirectory/subdirectory/subdirectory/subdirectory/subdirectory/subdirectory/subdirectory/subdirectory/ subdirectory/

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. Change to the /var/www/html/subdirectory/subdirectory/subdirectory/subdirectory/ subdirectory/subdirectory/subdirectory/subdirectory/subdirectory/subdirectory/subdirectory/subdirectory

Timeline

Published on: 03/14/2022 11:15:00 UTC
Last modified on: 08/15/2022 11:18:00 UTC

References