CVE-2021-4451: ninjafirewall Insecure Deserialization

Description

The NinjaFirewall plugin for WordPress is vulnerable to Authenticated PHAR Deserialization in versions up to, and including, 4.3.3. This allows authenticated attackers to perform phar deserialization on the server. This deserialization can allow other plugin or theme exploits if vulnerable software is present (WordPress, and NinjaFirewall).

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CVSS v3.1 Score

6.6

MEDIUM

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

Weakness Type (CWE)

CWE-502 Deserialization of Untrusted Data

Affected Products

Vendor	Product	Versions
nintechnet	ninjafirewall	< 4.3.3

References

Advisories & Patches

https://blog.nintechnet.com/security-issue-fixed-in-ninjafirewall-wp-edition/

Other References

https://www.wordfence.com/threat-intel/vulnerabilities/id/1a1fc6c9-50cd-40fd-a777-9eed98aab797?source=cve

Frequently Asked Questions

What is CVE-2021-4451? +

The NinjaFirewall plugin for WordPress is vulnerable to Authenticated PHAR Deserialization in versions up to, and including, 4.3.3. This allows authenticated attackers to perform phar deserialization on the server. This deserialization can allow other plugin or theme exploits if vulnerable software is present (WordPress, and NinjaFirewall). It has a CVSS v3.1 base score of 6.6 (MEDIUM).

How severe is CVE-2021-4451? +

CVE-2021-4451 has a CVSS v3.1 score of 6.6 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2021-4451? +

CVE-2021-4451 affects products from nintechnet, specifically: ninjafirewall. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2021-4451? +

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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