After a year of development the release of the spam filtering platform — . SpamAssassin implements a comprehensive approach to decision-making regarding blocking: messages undergo a series of checks (context analysis, blacklists and whitelists DNSBL, trainable Bayesian classifiers, signature checks, sender authentication via SPF and DKIM, etc.). After evaluating the message through various methods, a certain weight coefficient is accumulated. If the calculated coefficient exceeds a certain threshold, the message is blocked or marked as spam. Automatic rule update tools are supported. The package can be used on both client and server systems. SpamAssassin's code is written in Perl and is distributed under the Apache license.
of the new release:
- A new plugin OLEVBMacro has been added, designed to detect OLE macros and VB code within documents;
- Increased speed and security of scanning large emails with the body_part_scan_size and
rawbody_part_scan_size settings; - Support for the ‘nosubject’ flag has been added to the email body processing rules (body) to stop searching for the Subject header as part of the text in the email body;
- For security reasons, the option ‘sa-update —allowplugins’ is now deprecated;
- A new keyword ‘subjprefix’ has been added to the settings to append a prefix to the email subject when a rule is triggered. The templates now include a tag ‘_SUBJPREFIX_’, reflecting the value of the ‘subjprefix’ setting;
- The DNSEval plugin has been enhanced with the rbl_headers option to specify headers that should be checked against RBL lists;
- A check_rbl_ns_from function has been added to verify the DNS server in the RBL list. A check_rbl_rcvd function has been added to check domains or IP addresses from all Received headers in the RBL;
- The check_hashbl_emails function has received options to determine which headers should be checked in RBL or ACL;
- A check_hashbl_bodyre function has been added to search the email body using a regular expression and verify found matches in the RBL;
- A check_hashbl_uris function has been added to identify URLs in the email body and verify them in the RBL;
- A vulnerability (CVE-2018-11805) has been addressed, allowing the execution of system commands from CF files (SpamAssassin configuration files) without reporting their execution;
- A vulnerability (CVE-2019-12420) has been fixed, which could be exploited to cause a denial of service when processing an email with a specially crafted Multipart section.
SpamAssassin developers have also announced the preparation of version 4.0, which will include full built-in UTF-8 processing. Publication of rules based on the SHA-1 algorithm will be discontinued on March 1, 2020, as SHA-256 and SHA-512 hash functions replace SHA-1 in the 3.4.2 release.
Source: opennet.ru
