Unrestricted Upload of File with Dangerous Type in Windu CMS

published 2026-07-20 3mo ago modified 2026-10-24 18d ago also EUVD-2026-45945

cvss: 5.3; version 4.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.6%; EPSS 0.6% chance of exploitation in 30 days, percentile 50%
public exploits: 0; none known

Windu CMS does not validate types of uploaded files. An authenticated attacker can upload arbitrary files, including PHP. This can lead to Remote Code Execution.

Because vendor contact attempts were unsuccessful, the vulnerability has only been confirmed in version 4.1 but may also affect other versions.

Is CVE-2026-57311 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 3mo ago (2026-07-20)

Exploit prediction

0.63% chance of exploitation in the next 30 days, higher than 50% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by	version	score	vector
CNA	4.0	5.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:L/SI:L/SA:L
CNA	4.0	5.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:L/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

JCD Windu CMS

Classification

Weakness

CWE-434 Unrestricted Upload of File with Dangerous Type

References

cert.pl /posts/2026/07/CVE-2026-57309
third-party-advisory
windu.org
product

Sources

CVE List CVE-2026-57311
NVD CVE-2026-57311

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