# CVE-2026-4337: Unrestricted Upload of File in PuMuKIT application

Status: published. Published: 2026-10-27. Updated: 2026-11-04.

Unrestricted Upload of File with Dangerous Type vulnerability in the PuMuKIT application allows a unauthenticated user to upload any type of file to the server, and to any path where the web server user has write permissions. This could also allow them to delete files.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- PuMuKIT / PuMuKIT: current version (affected). Source: CNA: INCIBE

## Severity and prioritization

- CVSS 4.0: 8.8 (high); CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:H/SC:L/SI:L/SA:L; source: CNA: INCIBE

- CISA KEV: No listing in collected sources

- EPSS: 0.33% as of 2026-11-04; percentile 25.74%

- SSVC: exploitation none; automatable yes; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-434

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://www.incibe.es/en/incibe-cert/notices/aviso/unrestricted-upload-file-pumukit-application (CNA: INCIBE)

## Provenance

- CNA: INCIBE: https://www.cve.org/CVERecord?id=CVE-2026-4337; retrieved 2026-11-04; source updated 2026-11-04

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-4337; retrieved 2026-11-04; source updated Not reported

Revision: 6d1eb250c55af73a304f9a212023a30fb73829856f7cb7964f7802ebad16aa6b

Canonical: https://y2.dev/cve/CVE-2026-4337

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- OpenAPI: https://y2.dev/api/openapi.yaml. Agent access metadata: https://y2.dev/cve/agent.json.

Collected public records only. Check source status for coverage and freshness.