OpenPrinting CUPS is an open source printing system for Linux and other Unix-like operating systems. In versions 2.4.16 and prior, a local unprivileged user can coerce cupsd into authenticating to an attacker-controlled localhost IPP service with a reusable Authorization: Local ... token. That token is enough to drive /admin/ requests on localhost, and the attacker can combine CUPS-Create-Local-Printer with printer-is-shared=true to persist a file:///... queue even though the normal FileDevice policy rejects such URIs.
Printing to that queue gives an arbitrary root file overwrite; the PoC below uses that primitive to drop a sudoers fragment and demonstrate root command execution. At time of publication, there are no publicly available patches.
Attack Parameters
Impact Assessment
CVSS Vector v4.0
Weakness Type (CWE)
Vulnerable Products 1
| Configuration | From (including) | Up to (excluding) |
|---|---|---|
|
Openprinting Cups
cpe:2.3:a:openprinting:cups:*:*:*:*:*:*:*:*
|
— |
<= 2.4.16
|