CVE-2026-87876

Two case-insensitive comparisons on request-derived usernames outside the main authorization path in CUPS's scheduler (printer ACL validation and private-attribute filtering) could allow bypass of username-based access controls in certain configurations.

CVSS v3 3.0 LOW

3.0^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.5 / Impact : 1.4

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/errata/RHSA-2026:67568
https://access.redhat.com/security/cve/CVE-2026-87876
https://bugzilla.redhat.com/show_bug.cgi?id=2530991
https://github.com/OpenPrinting/cups/commit/88e67c00c130a45f3a1edf36686f7a0b2982fef8
https://github.com/OpenPrinting/cups/commit/f56844dbe4a54a9f8e1aeb3b913fbee614156bdb
https://github.com/OpenPrinting/cups/security/advisories/GHSA-r8jp-q6fh-g5r2
https://github.com/OpenPrinting/cups/security/advisories/GHSA-r8jp-q6fh-g5r2

Configurations

No configuration.

History

21 Sep 2026, 12:17

Type	Values Removed	Values Added
References		() https://access.redhat.com/errata/RHSA-2026:67568 -

Information

Published : 2026-09-09 17:17

Updated : 2026-10-21 21:20

NVD link : CVE-2026-87876

Mitre link : CVE-2026-87876

CVE.ORG link : CVE-2026-87876

JSON object : View

Products Affected

No product.

CWE

CWE-178

Improper Handling of Case Sensitivity

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