What is CVE-2026-57311?
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.
The record classifies CVE-2026-57311 under weakness class CWE-434. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 100 days ago.
Severity and exploitation probability
- CVSS v4.0 base score
- 5.3 — Medium (derived from score)
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 - EPSS (FIRST)
- 0.3% probability of exploitation in the next 30 days, higher than 29.7% of all scored CVEs
- CISA KEV
- Not listed in the CISA Known Exploited Vulnerabilities catalog
- Threadlinqs priority
- 3.8/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- Published
- 2026-07-20
Is CVE-2026-57311 being exploited?
No public exploitation evidence for CVE-2026-57311 is recorded in the sources Threadlinqs tracks — CISA KEV, Exploit-DB, public proof-of-concept repositories and ProjectDiscovery Nuclei — as of 2026-07-20. That is an absence of evidence in those feeds, not a guarantee that the vulnerability is unexploited.
Affected products and versions
- JCD: Windu CMS
How to fix CVE-2026-57311
No vendor patch reference has been recorded for CVE-2026-57311 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.
Threat activity tracking CVE-2026-57311
1 tracked threat in the Threadlinqs corpus references CVE-2026-57311, either in the campaign’s CVE list or as an indicator on the campaign record.
Sources
Enriched from CVE.org, NVD, FIRST EPSS, GitHub Security Advisories. Last verified by Threadlinqs on . This product uses the NVD API but is not endorsed or certified by the NVD.