CVE-2021-28998
File upload vulnerability in CMS Made Simple through 2.2.15 allows remote authenticated attackers to gain a webshell via a crafted phar file.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.29%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
File upload vulnerability in CMS Made Simple through 2.2.15 allows remote authenticated attackers to gain a webshell via a crafted phar file.
- CVSS 3.1
- 7.2 HIGHCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 1.29% probability · 70th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-434
- Affected
- cmsmadesimple/cms made simple
- Source
- cve@mitre.org
EPSS 1.3% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://github.com/beerpwn/CVE/blob/master/cms_made_simple_2021/file_upload_RCE/File_upload_to_RCE.mdExploit
- https://seclists.org/fulldisclosure/2021/Mar/50Mailing List, Third Party Advisory
- https://github.com/beerpwn/CVE/blob/master/cms_made_simple_2021/file_upload_RCE/File_upload_to_RCE.mdExploit
- https://seclists.org/fulldisclosure/2021/Mar/50Mailing List, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.