cmseasy V7.7.5_20211012 is affected by an arbitrary file write vulnerability.

published 2022-05-17 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-29607

cvss: 8.8; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 1.8%; EPSS 1.8% chance of exploitation in 30 days, percentile 78%
public exploits: 0; none known

cmseasy V7.7.5_20211012 is affected by an arbitrary file write vulnerability. Through this vulnerability, a PHP script file is written to the website server, and accessing this file can lead to a code execution vulnerability.

Exploit prediction

1.75% chance of exploitation in the next 30 days, higher than 78% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

jdr2021.github.io https://jdr2021.github.io/2021/10/14/CmsEasy_7.7.5_20211012%E5%AD%98%E5%9C%A8%E4%BB%BB%E6%84%8F%E6%96%87%E4%BB%B6%E5%86%99%E5%85%A5%E5%92%8C%E4%BB%BB%E6%84%8F%E6%96%87%E4%BB%B6%E8%AF%BB%E5%8F%96%E6%BC%8F%E6%B4%9E/ referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.1	8.8	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	6.5	AV:N/AC:L/Au:S/C:P/I:P/A:P

Classification

Weakness

CWE-22 Improper Limitation of a Pathname to a Restricted Directory

References

jdr2021.github.io /2021/10/14/CmsEasy_7.7.5_20211012%E5%AD%98%E5%9C%A8%E4%BB%BB%E6%84%8F%E6%96%87%E4%BB%B6%E5%86%99%E5%85%A5%E5%
exploit, third-party-advisory

Sources

CVE List CVE-2021-42643
NVD CVE-2021-42643

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary