WP Chill Passster: Missing authorization allows broken access control
Summary
The WordPress plugin Passster (package content-protector) up to and including version 4.3.20 contains a missing authorization check, classified as Broken Access Control. An unauthenticated remote attacker may be able to read content that is meant to be protected by a password without entering it. Only confidentiality is rated as affected; integrity and availability are not. The vulnerability is rated medium (CVSS 5.3) and no exploitation has been reported.
Affected
- WP Chill Passster (WordPress plugin content-protector) versions 0 through 4.3.20
Fixed in
- Version 4.3.21 (Patchstack lists 4.3.21 as the patched version)
Workaround
- Unknown: no vendor-documented interim mitigation was found.
- Until the update is applied, review which pages rely on Passster and consider restricting access to them at web server or firewall level.
Exploitation
- Not known to be exploited; not listed in CISA KEV.
- CISA SSVC: Exploitation none, automatable yes, technical impact partial.
- No public proof of concept found.
Our recommendation
- Inventory WordPress sites running Passster and check the installed version.
- Update Passster to version 4.3.21 or later.
- After the update, verify that protected pages still require the password.
- Prioritise sites that protect confidential client documents or member areas.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Patchstack advisory patchstack.com
- CVE Record CVE-2026-121574 www.cve.org
- OffSeq Radar radar.offseq.com
- Strix CVE details www.strix.ai
- WordPress.org plugin listing wordpress.org
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 11 Nov 2026, 17:52.
Original description (NVD)
Missing Authorization vulnerability in WP Chill Passster content-protector allows Exploiting Incorrectly Configured Access Control Security Levels.This issue affects Passster: from n/a through 4.3.20.
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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