OpenPrinting CUPS up to 2.4.16 on Linux authorization

Summaryinfo

A vulnerability has been found in OpenPrinting CUPS up to 2.4.16 on Linux and classified as problematic. Affected is an unknown function. The manipulation leads to authorization. This vulnerability is documented as CVE-2026-27447. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in OpenPrinting CUPS up to 2.4.16 on Linux. It has been rated as problematic. This issue affects an unknown part. The manipulation with an unknown input leads to a authorization vulnerability. Using CWE to declare the problem leads to CWE-863. The product 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. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

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.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-27447 since 02/19/2026. The exploitation is known to be difficult. The attack may be initiated remotely. The exploitation needs additional levels of successful authentication. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 07/06/2026).

The vulnerability scanner Nessus provides a plugin with the ID 304969 (Linux Distros Unpatched Vulnerability : CVE-2026-27447), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at Tenable (304969) and CERT Bund (WID-SEC-2026-0947). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

• Amazon Linux 2
• Fedora Linux
• Ubuntu Linux
• SUSE Linux
• SUSE openSUSE
• Microsoft Azure Linux
• Open Source CUPS

Productinfo

Type

• Printing Software

Vendor

• OpenPrinting

Name

• CUPS

Version

• 2.4.0
• 2.4.1
• 2.4.2
• 2.4.3
• 2.4.4
• 2.4.5
• 2.4.6
• 2.4.7
• 2.4.8
• 2.4.9
• 2.4.10
• 2.4.11
• 2.4.12
• 2.4.13
• 2.4.14
• 2.4.15
• 2.4.16

Website

• Product: https://github.com/OpenPrinting/cups/

CPE 2.3info

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CPE 2.2info

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Entryinfo

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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