Type Confusion in cups - #VU157266
Published: October 22, 2026
Vulnerability identifier: #VU157266
CSH Severity: Low
CVSS v4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-843
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to cause a denial of service by terminating the CUPS scheduler and interrupting the print queues and IPP services it manages.
The vulnerability exists due to type confusion in the cupsd create_subscriptions() and add_job_subscriptions() validation paths when processing the notify-natural-language IPP subscription attribute. A local user can send a specially crafted local IPP request containing a non-language value that is incorrectly interpreted as a NUL-terminated string during error-response generation, triggering an invalid or out-of-bounds read to terminate the scheduler. Repeated requests can sustain the denial of service.
Affected software
cups
Remediation
Install security update from vendor's website.
cups - update to 2.4.21