CVE-2026-5695: Microweber admin panel: unrestricted file upload to RCE

HIGH

Published September 23, 2026

CISO Take

CVE-2026-5695 is an unrestricted file upload flaw (CWE-434) in the Microweber administration panel. Authenticated users can upload arbitrary files, such as web shells, with no type validation, and the reporter demonstrated this with the EICAR test file. It is rated high severity, but there is no CVSS vector and no CISA KEV listing. SSVC says TRACK, no public exploit or Nuclei template exists, and the EPSS score of 0.003 (79th percentile) points to modest near-term exploitation likelihood. The package has 504 downstream dependents and 76 other CVEs, which signals a weak security track record, and the flaw becomes much more dangerous when chained with credential theft or the other Microweber flaws in the INCIBE advisory. Check the INCIBE-CERT notice for the fixed version and upgrade, restrict admin panel access to trusted networks, and review upload directories for unexpected executable files.

Sources:NVDEPSSOpenSSFATLASincibe.es

What is the risk?

Medium-high. Impact is potentially full server compromise, since uploaded files can lead to remote code execution. Exploitation requires authentication, which lowers likelihood. Exploit likelihood is low in the near term (EPSS 0.003, no public exploit, not in KEV, SSVC TRACK). Exposure is mainly Internet-facing admin panels with weak or reused credentials. The package risk score is 26/100, OpenSSF Scorecard is 6.7/10, and the project has 76 other CVEs, so repeat vulnerabilities are likely. The link to AI/ML systems is indirect (ml_ui category): the risk is host compromise of a web or CMS front end that may sit next to AI services or hold their credentials.

How does the attack unfold?

Initial Access

The attacker authenticates to the Microweber admin panel with stolen or weak credentials.

AML.T0012

Exploitation

The attacker uploads a malicious file through the unvalidated upload form.

AML.T0049

Execution

The attacker requests the uploaded file to run code on the server.

Impact

The server is fully compromised, exposing secrets and connected AI or data services.

Initial Access

The attacker authenticates to the Microweber admin panel with stolen or weak credentials.

AML.T0012

Exploitation

The attacker uploads a malicious file through the unvalidated upload form.

AML.T0049

Execution

The attacker requests the uploaded file to run code on the server.

Impact

The server is fully compromised, exposing secrets and connected AI or data services.

What systems are affected?

Package	Ecosystem	Vulnerable Range	Patched
Panel	pip	—	No patch
5.8KOpenSSF 6.5514 dependentsPushed 6d ago67% patched~15d to patchFull package profile →

Do you use Panel? You're affected.

How severe is it?

CVSS 3.1

N/A

EPSS

0.4%

chance of exploitation in 30 days

Higher than 35% of all CVEs

Source: EPSS v3 — FIRST.org

Exploitation Status

No known exploitation

Sophistication

Trivial

What should I do?

1 step

1) Apply the vendor fix referenced in the INCIBE-CERT advisory (the affected and patched ranges are not given in the data, so confirm the version with the vendor). 2) Restrict the admin panel to VPN or an IP allowlist and enforce MFA and strong, unique credentials. 3) Enforce server-side allowlists for file extension, MIME type and content, store uploads outside the web root, and disable script execution in upload directories. 4) Detection: audit upload directories for new .php, .phtml or other executable files, alert on web server processes spawning shells, and review admin login anomalies and upload logs. 5) Run antivirus or EDR scans on upload paths. 6) Rotate secrets on any host where suspicious uploads are found.

What does CISA's SSVC say?

DecisionTrack

Exploitationnone

AutomatableNo

Technical Impacttotal

Source: CISA Vulnrichment (SSVC v2.0). Decision based on the CISA Coordinator decision tree.

How is it classified?

Code ExecutionFrameworkAML.T0012- Valid Accounts AML.T0049- Exploit Public-Facing Application

Which compliance frameworks are affected?

This CVE is relevant to:

ISO 42001

A.10.3-Suppliers

NIST AI RMF

MANAGE 2.3-Responses to previously unknown risks

OWASP LLM Top 10

LLM03-Supply Chain

Frequently Asked Questions

What is CVE-2026-5695?

Is CVE-2026-5695 actively exploited?

No confirmed active exploitation of CVE-2026-5695 has been reported, but organizations should still patch proactively.

How to fix CVE-2026-5695?

1) Apply the vendor fix referenced in the INCIBE-CERT advisory (the affected and patched ranges are not given in the data, so confirm the version with the vendor). 2) Restrict the admin panel to VPN or an IP allowlist and enforce MFA and strong, unique credentials. 3) Enforce server-side allowlists for file extension, MIME type and content, store uploads outside the web root, and disable script execution in upload directories. 4) Detection: audit upload directories for new .php, .phtml or other executable files, alert on web server processes spawning shells, and review admin login anomalies and upload logs. 5) Run antivirus or EDR scans on upload paths. 6) Rotate secrets on any host where suspicious uploads are found.

What systems are affected by CVE-2026-5695?

This vulnerability affects the following AI/ML architecture patterns: Web admin panels / CMS front ends, ML user interfaces, Web applications integrated with AI services.

What is the CVSS score for CVE-2026-5695?

No CVSS score has been assigned yet.

What is the AI security impact?

Affected AI Architectures

Web admin panels / CMS front endsML user interfacesWeb applications integrated with AI services

MITRE ATLAS Techniques

AML.T0012Valid Accounts

AML.T0049Exploit Public-Facing Application

Compliance Controls Affected

ISO 42001: A.10.3

NIST AI RMF: MANAGE 2.3

OWASP LLM Top 10: LLM03

What are the technical details?

Original Advisory

Arbitrary file upload vulnerability due to a lack of proper validation in upload forms. This allows authenticated users to upload files to the server without restrictions. An attacker could exploit this flaw to execute malicious code remotely (demonstrated by uploading the EICAR test file), which could result in the system being completely compromised.

Exploitation Scenario

An attacker obtains valid Microweber admin or editor credentials through phishing, credential stuffing or a companion flaw from the same advisory. They log in and use the upload form to submit a web shell, since the form does not validate file type. They request the uploaded file directly to get code execution as the web server user. They then harvest environment variables and configuration files for database and AI service API keys, and pivot toward connected ML or LLM services.

Weaknesses (CWE)

CWE-434Unrestricted Upload of File with Dangerous Type

CWE-434 — Unrestricted Upload of File with Dangerous Type: The product allows the upload or transfer of dangerous file types that are automatically processed within its environment.

[Architecture and Design] Generate a new, unique filename for an uploaded file instead of using the user-supplied filename, so that no external input is used at all.[REF-422] [REF-423]
[Architecture and Design] When the set of acceptable objects, such as filenames or URLs, is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames or URLs, and reject all other inputs.

Source: MITRE CWE corpus.