MCMS vulnerable to arbitrary code execution via crafted thumbnail

published 2023-05-08 3 y ago modified 2026-06-17 4 mo ago also GHSA-293v-5329-36wp , EUVD-2023-1444

cvss: 8.8; version 3.1, CNA
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

File upload vulnerability in MCMS 5.0 allows attackers to execute arbitrary code via a crafted thumbnail. A different vulnerability than CVE-2022-31943.

CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: total
Assessed: 21 mo ago (2025-01-29)

Exploit prediction

0.92% 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/ming-soft/MCMS/issues/42 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CISA ADP	3.1	8.8	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD	3.1	8.8	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CNA	3.1	8.8	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
GitHub	3.1	8.8	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected packages

ecosystem	package	affected	fixed in
maven	net.mingsoft:ms-mcms	<=5.0.0	no fix listed

Classification

Weakness

CWE-434 Unrestricted Upload of File with Dangerous Type

References

github.com /ming-soft/MCMS/issues/42
web, exploit, issue-tracking
github.com /ming-soft/MCMS
package, product
nvd.nist.gov /vuln/detail/CVE-2020-22755
advisory

Sources

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