What’s Vulnerable › Vulnerabilities

CVE-2021-20104

• Severity: high (CVSS 8.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 2.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-06-29 · updated 2026-06-17
• Weakness: CWE-434

Description

Machform prior to version 16 is vulnerable to unauthenticated remote code execution due to insufficient sanitization of file attachments uploaded with forms through upload.php.

Affected products

• AppNitro Machform: before 16 — fixed in 16

How to fix

Upgrade to a fixed version: AppNitro Machform 16. Check the vendor advisory for mitigations.

References

• https://www.tenable.com/security/research/tra-2021-25%2Chttps://www.machform.com/blog-machform-16-released/
• https://www.tenable.com/security/research/tra-2021-25%2Chttps://www.machform.com/blog-machform-16-released/

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