This plugin requires SpamAssassin 4.0.2 or newer.
This plugin looks for URLs redirected by a list of URL redirector services. Upon finding a matching URL, the plugin will send a HTTP request to the redirector service and retrieve the Location-header which points to the actual redirected URL. It then adds this URL to the list of URIs extracted by SpamAssassin which can then be accessed by URI rules and plugins such as URIDNSBL. The plugin will also follow chained redirections, where a redirected URL redirects to another redirector.
The plugin looks for URLs that carry parameters typical of redirector services; the parameters are matched using the url_redirector_params regexp and the redirector domains defined with url_redirector. When a matching URL is found, it sends an HTTP request to the redirector, reads the Location header to find the actual destination, and adds that destination URL to the list of URIs extracted by SpamAssassin so URI rules and plugins such as URIDNSBL can score it. The plugin runs before priority 0 so the destination URLs are available to the normal URI rules, and the lookups are cached (url_redirector_cache_type).
| Area | Rule name | Description | Default scores |
|---|---|---|---|
| meta | __GEN_REDIR_URL |
Message has one or more redirected URLs | -- |
| body | REDIR_URL_CHAINED |
Message has redirected URL chained to other redirectors | 0.01 |
| body | REDIR_URL_MAXCHAIN |
Message has redirected URL that causes too many redirections | 0.01 |
| body | REDIR_URL_LOOP |
Message has redirected URL that loops back to itself | 0.01 |