CVE-2026-27447 (GCVE-0-2026-27447)
Vulnerability from cvelistv5 – Published: 2026-04-03 21:11 – Updated: 2026-04-06 18:50
VLAI
EPSS
VEX
Title
OpenPrinting CUPS: Authorization bypass via case-insensitive group-member lookup
Summary
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.
Severity
4.8 (Medium)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-06 18:49 UTC
CWE
- CWE-863 - Incorrect Authorization
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/OpenPrinting/cups/security/adv… | x_refsource_CONFIRM |
| https://github.com/OpenPrinting/cups/commit/88516… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| OpenPrinting | cups |
Affected:
<= 2.4.16
|
guessed |
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