Improper Neutralization of Special Elements in Output Used by a Downstream Component in cups - CVE-2026-55453

Detailed vulnerability description

The vulnerability allows a remote attacker to execute arbitrary code.

The vulnerability exists due to improper neutralization of special elements in output used by a downstream component in the CUPS ipp backend status reporting path and scheduler PPD update handling when processing text printer-status attributes from a remote IPP printer. A remote attacker can return a crafted printer-status attribute containing injected newline characters and a forged PPD status line to execute arbitrary code.

Successful exploitation requires a CUPS queue that points to an attacker-controlled or compromised IPP printer, a Foomatic-backed PPD or filter profile that invokes foomatic-rip, and a later print job that uses the modified PPD. The demonstrated code execution occurs as user lp.

How to mitigate CVE-2026-55453

Sources

• https://github.com/OpenPrinting/cups/security/advisories/GHSA-7hqf-mfhx-7r3v