Description
The Leaky Paywall WordPress plugin is vulnerable to Stored Cross-Site Scripting due to insufficient input validation and sanitization via the ~/class.php file which allowed attackers with administrative user access to inject arbitrary web scripts, in versions up to and including 4.16.5. This affects multi-site installations where unfiltered_html is disabled for administrators, and sites where unfiltered_html is disabled.
References (3)
Core 3
Core References
Patch, Third Party Advisory x_refsource_misc
https://plugins.trac.wordpress.org/changeset/2615195/leaky-paywall/trunk/class.php
Third Party Advisory x_refsource_misc
https://wordfence.com/vulnerability-advisories/#CVE-2021-39357
Exploit, Third Party Advisory x_refsource_misc
https://github.com/BigTiger2020/word-press/blob/main/Leaky%20Paywall.md
Scores
CVSS v3
5.5
EPSS
0.0065
EPSS Percentile
71.0%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-79
Status
published
Products (1)
zeen101/leaky_paywall
< 4.16.5
Published
Oct 21, 2021
Tracked Since
Feb 18, 2026