Apple has released Security Update 2004-01-26. OS X 10.3 (Client or Server) users will see updates to the Apache webserver, the Classic environment, Mail.app, Safari, and Windows File Sharing. OS X 10.2 users (Client or Server) will see updates to all of the same components except Windows File Sharing. The update for 10.3 and 10.2 users also incorporates the features added by Security Update 2003-12-19. There is even an update for any remaining OS X 10.1 users, bringing security enhancements to Mail.app. From Apple:

Security Update 2004-01-26 delivers a number of security enhancements and is recommended for all Macintosh users. This update includes the following components:

• Apache 1.3
• Classic
• Mail
• Safari
• Windows File Sharing

Additionally, Security Update 2003-12-19 has been incorporated into this security update. Those components are:

• AFP Server
• ASN.1 Decoding for PKI
• cd9660.util
• Directory Services
• fetchmail
• fs_usage
• rsync
• System Initialization

You can find the update in the Software Update pane. OS X 10.3 users are looking at a 7.8MB download, 4.8MB for 10.2 users, and 2.2MB for 10.1 users. The updates can also be found at Appleis site.