Auth bypass in Passster
CVE-2026-17559
The Passster WordPress plugin before 4.3.9 does not correctly match its own public endpoint paths when deciding which REST API requests may bypass global password protection, comparing them as an unanchored substring of the request URI rather than against the resolved route, allowing an unauthenticated attacker to read the content of globally password-protected posts and pages.
Vulnerability class: Broken Access Control
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.
Affected products
- Unknown Passster
Weakness classification (CWE)
References
- contact@wpscan.com (technical-description, exploit, vdb-entry)
Frequently asked questions
- What is CVE-2026-17559?
- CVE-2026-17559 is a medium-severity vulnerability in Passster, classified under Incorrect Authorization. CVSS score: 5.3/10. Published 2026-08-21.
- How severe is CVE-2026-17559?
- Medium severity. CVSS v3 base score is 5.3 out of 10.