External risk intelligence

Fast Checkin Arbitrary File Upload Vulnerability

CVE advisorySeverity: CRITICAL (CVSS 9.8)

CVE-2022-47769

The product is a web application designed for check-in processes. Such applications are commonly deployed as internet-facing services to allow users or guests to perform check-in operations remotely or via public-facing kiosks.

Unrestricted File Upload

Serinf Fast Checkin

1.0

Halo Surface Signal: 4 out of 5 — likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

An arbitrary file write vulnerability exists in Fast Checkin version 1.0, a web application used for check-in processes. This flaw could allow unauthenticated attackers to upload malicious files, potentially leading to unauthorized access to the application's server. The main concern is to confirm if this specific technology is in use within the organization and assess any potential exposure.

Attackers can upload malicious files.
Confirms product usage and potential exposure.
Understand potential server access risks.

Attack Path

How an attacker could exploit the issue

An unauthenticated attacker can upload a malicious file to the web server through the application's web root. This file can then be used to execute commands on the server, potentially leading to full system compromise.

No authentication required.
Uploading malicious file to web root.
Server compromise via web shell.

Live Threat

Current exploitation, exposure, and threat context

An arbitrary file write vulnerability in Serenissima Informatica Fast Checkin could allow an unauthenticated attacker to upload a malicious file to the web root of the application. This may enable the attacker to execute commands on the server through a web shell, potentially impacting the application's availability and integrity.

Application server files.
Attacker uploads a malicious web shell.
Server compromise and potential data exposure.

Operational Fix

Recommended remediation, mitigation, and detection steps

Application owners are responsible for addressing this arbitrary file write vulnerability in Fast Checkin. The first practical step is to identify all instances of the affected technology, confirm business criticality and external reachability, and then assign ownership for remediation planning.

Application owners should own this issue.
Verify external reachability and business criticality.
Plan remediation based on confirmed risk.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

Halo Threat Intelligence helps prioritize remediation with Halo Surface Signal and H/A/L/O context. Start exposure validation with a free external attack surface trial.

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Frequently asked questions

What is Serenissima Informatica Fast Checkin?

Fast Checkin is a specialized web application developed by Serenissima Informatica to automate and manage guest registration processes. It is typically deployed as a service for hotels or public venues, allowing guests to complete check-in requirements digitally before or upon arrival. Because it handles sensitive arrival data, it often runs on web servers that need to interact with external guest networks.

What does CWE-434 mean for CVE-2022-47769?

CWE-434 refers to an Unrestricted Upload of File with Dangerous Type. In the context of this vulnerability, it means the application does not properly validate or restrict the types of files a user can upload. An attacker can exploit this weakness to place unauthorized scripts or malicious files directly into the application's web folder, which the server might then incorrectly process or execute as part of its normal operations.

How do attackers trigger this file write flaw?

The vulnerability is triggered when an attacker sends a crafted request to the application to upload a file to the web root. No authentication is needed to perform this action. It is important to note that simply visiting the site or performing legitimate check-in functions does not trigger the bug; the vulnerability specifically requires the intentional upload of a file designed to bypass the application's intended security controls.

Do I need to worry about external reachability?

Yes, you should prioritize investigating this if your instance is internet-facing. According to Halo Surface Signal, this software is often deployed as a public-facing service for remote guest operations. Any application exposed to the internet increases the risk that an unauthorized actor could discover and attempt to exploit the file upload weakness to gain control over the underlying server.

When should I start responding to this?

You should begin by immediately auditing your environment to locate any instances of Fast Checkin version 1.0. Once identified, evaluate whether the application is accessible from the internet or restricted to internal networks. After establishing the scope and business criticality, coordinate with the application owners to plan remediation steps and prevent potential unauthorized access to your server infrastructure.

References

serenissima.com/

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.