CVE-2021-28998 json
File upload vulnerability in CMS Made Simple through 2.2.15 allows remote authenticated attackers to gain a webshell via a crafted phar fil…
published 2023-05-08 3 y ago modified 2026-06-17 4 mo ago also EUVD-2021-15645
- cvss
- 7.2
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.3%
- EPSS 1.3% chance of exploitation in 30 days, percentile 70%
- public exploits
- 0
- none known
Summary
File upload vulnerability in CMS Made Simple through 2.2.15 allows remote authenticated attackers to gain a webshell via a crafted phar file.
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- total
- Assessed
- 21 mo ago
Exploit prediction
1.29% chance of exploitation in the next 30 days, higher than 70% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/beerpwn/CVE/blob/master/cms_made_simple_2021/file_upload_RCE/File_upload_to_RCE.md referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CISA ADP | 3.1 | 7.2 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H |
| NVD | 3.1 | 7.2 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H |
| CNA | 3.1 | 7.2 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H |
Classification
- Weakness
-
- CWE-434 Unrestricted Upload of File with Dangerous Type
References
-
github.com
/beerpwn/CVE/blob/master/cms_made_simple_2021/file_upload_RCE/File_upload_to_RCE.md
exploit
-
seclists.org
/fulldisclosure/2021/Mar/50
mailing-list, third-party-advisory
Sources
- CVE List CVE-2021-28998
- NVD CVE-2021-28998
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