CVE-2026-17559: medium-severity vulnerability in Passster
Content Protector (Passster) < 4.3.9 - Unauthenticated Protected Content Disclosure via REST Path Allowlist Bypass
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
33Vexday Risk Score
No sign of exploitation. It has a public proof of concept.
ssvc Attendcvss 5.3epss 0.4%
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Affected products
Unknown · Passsterpublic PoCs found — 1
cve_referencewpscan.com/vulnerability/28a48c1c-e162-4e8a-b450-5568fb3a3fc8/unverified⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
Related CVEs — Passster
In the same product, most dangerous first.
CVE-2021-24881HIGHPassster < 3.5.5.9 - Protection Bypass & Arbitrary Post AccessEPSS 0.8%CVE-2022-3206MEDIUMPassster < 3.5.5.5.2 - Insecure Storage of PasswordEPSS 0.6%CVE-2026-16604HIGHContent Protector (Passster) < 4.3.6 - Unauthenticated Protected Content Disclosure via Content-Lock Block data-content AttributeEPSS 0.4%CVE-2026-16603HIGHContent Protector (Passster) < 4.3.6 - Unauthenticated Category-Locked Content Disclosure via Core REST APIEPSS 0.4%CVE-2026-16602HIGHContent Protector (Passster) < 4.3.6 - Unauthenticated Non-Public Post Content Disclosure via Captcha REST EndpointEPSS 0.4%CVE-2021-24837—Passster < 3.5.5.8 - Contributor+ Stored Cross-Site ScriptingEPSS 0.4%