CVE-2021-39357

Public Exploit
Leaky Paywall <= 4.16.5 Authenticated Stored Cross-Site Scripting

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.

Remediation

Solution:

  • Uninstall WordPress plugin from site.

Category

5.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.45%
Third-Party Advisory github.com Third-Party Advisory wordpress.org Third-Party Advisory wordfence.com
Affected: Leaky Paywall Leaky Paywall
Published at:
Updated at:

References

Link Tags
https://plugins.trac.wordpress.org/changeset/2615195/leaky-paywall/trunk/class.php third party advisory patch
https://wordfence.com/vulnerability-advisories/#CVE-2021-39357 third party advisory
https://github.com/BigTiger2020/word-press/blob/main/Leaky%20Paywall.md third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2021-39357?
CVE-2021-39357 has been scored as a medium severity vulnerability.
How to fix CVE-2021-39357?
To fix CVE-2021-39357: Uninstall WordPress plugin from site.
Is CVE-2021-39357 being actively exploited in the wild?
It is possible that CVE-2021-39357 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-39357?
CVE-2021-39357 affects Leaky Paywall Leaky Paywall.
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