CUPS 2.4.16 Auth Bypass via caseinsensitive username comparison
CVE-2026-27447 Published on April 3, 2026
OpenPrinting CUPS: Authorization bypass via case-insensitive group-member lookup
OpenPrinting CUPS is an open source printing system for Linux and other Unix-like operating systems. In versions 2.4.16 and prior, CUPS daemon (cupsd) contains an authorization bypass vulnerability due to case-insensitive username comparison during authorization checks. The vulnerability allows an unprivileged user to gain unauthorized access to restricted operations by using a user with a username that differs only in case from an authorized user. At time of publication, there are no publicly available patches.
Vulnerability Analysis
CVE-2026-27447 can be exploited with network access, requires user interaction and user privileges. This vulnerability is consided to have a high level of attack complexity. The potential impact of an exploit of this vulnerability is considered to have a high impact on confidentiality, with no impact on integrity, and no impact on availability.
Weakness Type
What is an AuthZ Vulnerability?
The software performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check. This allows attackers to bypass intended access restrictions.
CVE-2026-27447 has been classified to as an AuthZ vulnerability or weakness.
Products Associated with CVE-2026-27447
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