CVE-2021-28428 json
File upload vulnerability in HorizontCMS before 1.0.0-beta.3 via uploading a .htaccess and *.hello files using the Media Files upload funct…
published 2022-04-05 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-15107
- cvss
- 9.8
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.2%
- EPSS 1.2% chance of exploitation in 30 days, percentile 69%
- public exploits
- 0
- none known
Summary
File upload vulnerability in HorizontCMS before 1.0.0-beta.3 via uploading a .htaccess and *.hello files using the Media Files upload functionality. The original file upload vulnerability (CVE-2020-27387) was remediated by restricting the PHP extensions; however, we confirmed that the filter was bypassed via uploading an arbitrary .htaccess and *.hello files in order to execute PHP code to gain RCE.
Patch / fix
Exploit prediction
1.24% chance of exploitation in the next 30 days, higher than 69% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 7.5 | AV:N/AC:L/Au:N/C:P/I:P/A:P |
Classification
- Weakness
-
- CWE-434 Unrestricted Upload of File with Dangerous Type
References
-
github.com
/ttimot24/HorizontCMS/commit/9c4d6827cbe96decec6834d53660e14ab2bf8838
patch, third-party-advisory
-
github.com
/ttimot24/HorizontCMS
product
Sources
- CVE List CVE-2021-28428
- NVD CVE-2021-28428
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