This is a series of exploits that bypass SAFER mode of Ghostscript.
The PoC codes shown below allow you to get command execution or file I/O at the privilege of the process even if Ghostscript is running on SAFER mode.
However, all of them bypass the protection by overwriting the security flags in systemdict therefore they have no longer effect against recent Ghostscript(>= 9.50) that have started employing the new SAFER implementation that prevents critical dictionaries from overwriting (refer to commit 79a06b).
CVE-2019-14811 is a .forceput
exposure from .pdf_hook_DSC_Creator
and 'ghostrule1.ps' is the exploit for it.
Credit: @hhc0null
CVE-2019-14812 is a .forceput
exposure from setuserparams
and 'ghostrule2.ps' is the exploit for it.
Credit: @hhc0null
CVE-2019-14813 is a .forceput
exposure from setsystemparams
and 'ghostrule3.ps' is the exploit for it.
Credit: @hhc0null
CVE-2019-10216 is a .forceput
exposure from buildfont1
and 'ghostrule4.ps' is the exploit for it.
Credit: Artifex Software and Netanel (Cloudinary) as the "original" reporter...???
I'm not so ethical thus I'm keeping the technique to grow its 'lifetime' <3
The name is from: