I tried to upgrade from Joomla 1.5.23 to 1.5.26 by following cPanel-specific instructions at http://docs.joomla.org/J2.5:Migrating_from_Joomla_1.5_to_Joomla_2.5#Review_the_Requirements
which referenced
http://docs.joomla.org/Uploading_and_extracting_an_archive_file_with_CPanel

I downloaded patches from
http://joomlacode.org/gf/download/frsrelease/16891/73384/Joomla_1.5.0_to_1.5.26-Stable-Patch_Package.zip
and
http://joomlacode.org/gf/download/frsrelease/16891/73386/Joomla_1.5.25_to_1.5.26-Stable-Patch_Package.tar.gz

When I tried to upload
Joomla_1.5.0_to_1.5.26-Stable-Patch_Package.tar.gz
or
Joomla_1.5.0_to_1.5.26-Stable-Patch_Package.zip

I get an error message from cPanel which says
C:\fakepath\Joomla_1.5.0_to_1.5.26-Stable-Patch_Package.zip: unknown Bytes complete FAILED! :Upload canceled: VIRUS DETECTED! (Access denied. ERROR)

I do not know if there is a virus in the patch (which would be really bad!) or if there is some bug with cPanel. Given how scary a virus in the patch is, I figured I had better report it.