CVE-2021-33224
CVE-2021-33224 is a critical-severity vulnerability in Umbraco Umbraco Forms with a CVSS 3.x base score of 9.8. 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: Critical (CVSS 3.x base score 9.8)
- EPSS exploit prediction: 1% (50th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-434
- Affected product: Umbraco Umbraco Forms
- Published:
- Last modified:
Description
File upload vulnerability in Umbraco Forms v.8.7.0 allows unauthenticated attackers to execute arbitrary code via a crafted web.config and asp file.
Frequently asked questions
- What is CVE-2021-33224?
- File upload vulnerability in Umbraco Forms v.8.7.0 allows unauthenticated attackers to execute arbitrary code via a crafted web.config and asp file.
- How severe is CVE-2021-33224?
- CVE-2021-33224 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-33224 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-33224?
- CVE-2021-33224 affects Umbraco Umbraco Forms. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-33224?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2021-33224 published?
- CVE-2021-33224 was published on 2023-02-24 and last updated on 2026-07-09.
References
Affected products (1)
- cpe:2.3:a:umbraco:umbraco_forms:8.7.0:*:*:*:*:*:*:*
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