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.
Attack Parameters
Attack Vector
Adjacent
Requires local network access
Attack Complexity
Low
Easy to exploit
Privileges Required
Low
Basic privileges needed
User Interaction
Required
User action required
Impact Assessment
Confidentiality
Low
Partial data leak
Integrity
None
No data modification
Availability
None
No disruption
CVSS Vector v3.1
Weakness Type (CWE)
References 5
https://access.redhat.com/security/cve/CVE-2026-87876
secalert@redhat.com
https://bugzilla.redhat.com/show_bug.cgi?id=2530991
secalert@redhat.com
https://github.com/OpenPrinting/cups/security/advisories/GHSA-r8jp-q6fh-g5r2
secalert@redhat.com
https://github.com/OpenPrinting/cups/commit/88e67c00c130a45f3a1edf36686f7a0b298…
secalert@redhat.com
https://github.com/OpenPrinting/cups/commit/f56844dbe4a54a9f8e1aeb3b913fbee6141…
secalert@redhat.com