CVE-2021-20104
CVE-2021-20104 is a high-severity vulnerability in Machform with a CVSS 3.x base score of 8.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-434.
Key facts
- Severity: High (CVSS 3.x base score 8.1)
- CVSS v2: 6.8
- EPSS exploit prediction: 2% (80th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-434
- Affected product: Machform
- Published:
- Last modified:
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.
Frequently asked questions
- What is CVE-2021-20104?
- 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.
- How severe is CVE-2021-20104?
- CVE-2021-20104 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-20104 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-20104?
- CVE-2021-20104 affects Machform. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-20104?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2021-20104 published?
- CVE-2021-20104 was published on 2021-06-29 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:machform:machform:*:*:*:*:*:*:*:*
More vulnerabilities in Machform
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- CVE-2018-6411 — Critical (CVSS 9.8): An issue was discovered in Appnitro MachForm before 4.2.3. When the form is set to filter a blacklist, it automatically…
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- CVE-2024-37765 — High (CVSS 8.8): Machform up to version 19 is affected by an authenticated Blind SQL injection in the user account settings page.
- CVE-2021-20102 — High (CVSS 8.8): Machform prior to version 16 is vulnerable to cross-site request forgery due to a lack of CSRF tokens in place.
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