CVE-2020-36854: XSS (CVSS 6.4)

Description

The Async JavaScript plugin for WordPress is vulnerable to Stored Cross-Site Scripting in versions up to, and including, 2.19.07.14. This is due to missing authorization checks on the aj_steps AJAX aciton along with a lack on sanitization on the settings saved via the function. This makes it possible for authenticated attackers with subscriber level permissions and above to inject malicious web scripts into a page that execute whenever a user accesses that page.

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CVSS v3.1 Score

6.4

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

Weakness Type (CWE)

CWE-79 Cross-site Scripting (XSS)

References

Other References

https://www.wordfence.com/blog/2020/02/site-takeover-campaign-exploits-multiple-zero-day-vulnerabilities/ https://www.wordfence.com/threat-intel/vulnerabilities/id/b133888c-7673-4796-917c-486bff1b6b12?source=cve

Frequently Asked Questions

What is CVE-2020-36854? +

The Async JavaScript plugin for WordPress is vulnerable to Stored Cross-Site Scripting in versions up to, and including, 2.19.07.14. This is due to missing authorization checks on the aj_steps AJAX aciton along with a lack on sanitization on the settings saved via the function. This makes it possible for authenticated attackers with subscriber level permissions and above to inject malicious web scripts into a page that execute whenever a user accesses that page. It has a CVSS v3.1 base score of 6.4 (MEDIUM).

How severe is CVE-2020-36854? +

CVE-2020-36854 has a CVSS v3.1 score of 6.4 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

How do I check if I'm vulnerable to CVE-2020-36854? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2020-36854