Check it out on version tracker.
Security Update 7-12-02 increases the security of the Software Update process for systems with Software Update client 1.4.5 or earlier. Packages presented via the Software Update mechanism are now cryptographically signed, and the new Software Update client 1.4.6 checks for a valid signature before installing new packages. Downloaded packages which do not contain a valid signature are deleted from the system.
Security Update 7-12-02 increases the security of the Software Update process for systems with Software Update client 1.4.5 or earlier. Packages presented via the Software Update mechanism are now cryptographically signed, and the new Software Update client 1.4.6 checks for a valid signature before installing new packages. Downloaded packages which do not contain a valid signature are deleted from the system.