Medium severity · published Aug 21, 2026
CVE-2026-17559
Content Protector (Passster) < 4.3.9 - Unauthenticated Protected Content Disclosure via REST Path Allowlist Bypass
5.3
CVSS
0.4%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 29% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PA
Passster ·
4.3.3 before 4.3.9 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-17559
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-17559
wpscan.com
https://wpscan.com/vulnerability/28a48c1c-e162-4e8a-b450-5568fb3a3fc8/
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