CVE-2020-20691 json
An issue in Monstra CMS v3.0.4 allows attackers to execute arbitrary web scripts or HTML via bypassing the file extension filter and upload…
published 2021-09-27 5 y ago modified 2026-06-17 4 mo ago also EUVD-2020-13476
- cvss
- 6.5
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.9%
- EPSS 0.9% chance of exploitation in 30 days, percentile 60%
- public exploits
- 0
- none known
Summary
An issue in Monstra CMS v3.0.4 allows attackers to execute arbitrary web scripts or HTML via bypassing the file extension filter and uploading crafted HTML files.
Exploit prediction
0.93% chance of exploitation in the next 30 days, higher than 60% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/monstra-cms/monstra/issues/461 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N |
| NVD | 2.0 | 5.8 | AV:N/AC:M/Au:N/C:P/I:P/A:N |
Classification
- Weakness
-
- CWE-434 Unrestricted Upload of File with Dangerous Type
References
-
github.com
/monstra-cms/monstra/issues/461
exploit, issue-tracking, third-party-advisory
Sources
- CVE List CVE-2020-20691
- NVD CVE-2020-20691
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