CVE-2025-46414: Authentication Bypass Vulnerability

CVE-2025-46414 Overview

CVE-2025-46414 is a critical authentication weakness affecting an EG4 Electronics product registered through a cloud-based API. The product does not limit the number of attempts for inputting the correct PIN associated with a registered device. An attacker who knows a valid device serial number can brute-force the PIN to gain unauthorized access. The API also returns clear feedback when the correct PIN is entered, which accelerates brute-force attacks. The flaw is classified under CWE-307: Improper Restriction of Excessive Authentication Attempts. The vendor remediated the issue through a server-side update on April 6, 2025.

Critical Impact
Remote attackers with a valid device serial number can brute-force the PIN over the network and obtain unauthorized control of a registered product without user interaction.

Affected Products

EG4 Electronics registered product (cloud-managed PIN authentication API)
Server-side authentication service for device registration
Any integration relying on the affected PIN verification endpoint

Discovery Timeline

April 6, 2025 - Vendor releases server-side update remediating the vulnerability
August 8, 2025 - CVE-2025-46414 published to the National Vulnerability Database
April 15, 2026 - Last updated in NVD database

Technical Details for CVE-2025-46414

Vulnerability Analysis

The vulnerability resides in the server-side API responsible for authenticating registered EG4 Electronics products using a PIN. The endpoint applies no rate limiting, account lockout, or throttling against repeated authentication failures. An attacker who possesses a valid device serial number can iterate through the PIN space programmatically until access is granted. The API compounds the issue by returning unambiguous success feedback when the correct PIN is submitted. This eliminates oracle ambiguity and allows automated tooling to definitively identify the correct credential. According to the CISA ICS Advisory ICSA-25-219-07, the flaw is network-exploitable and requires no privileges or user interaction.

Root Cause

The root cause is missing enforcement of authentication attempt limits on the PIN verification endpoint. The server treats each authentication attempt as an independent event. There is no per-serial-number counter, no exponential backoff, no CAPTCHA, and no temporary lockout after consecutive failures. Combined with a limited PIN keyspace, this design allows exhaustive enumeration within practical timeframes.

Attack Vector

An attacker first obtains or guesses a valid device serial number. Serial numbers are often printed on hardware, embedded in mobile applications, or recoverable from prior interactions. The attacker then issues automated PIN guesses to the registration API. Because the API distinguishes correct from incorrect submissions, the attacker can detect success on the first valid PIN and pivot to authenticated device access.

No verified proof-of-concept code is publicly available. See the CISA ICS Advisory ICSA-25-219-07 for additional technical context.

Detection Methods for CVE-2025-46414

Indicators of Compromise

High volumes of failed PIN authentication requests targeting a single device serial number from one or more source IP addresses.
Sequential or dictionary-style PIN values submitted to the registration API within short time windows.
Successful PIN authentication immediately following a burst of failed attempts on the same serial number.
Unexpected device control commands or configuration changes following authentication events.

Detection Strategies

Aggregate authentication logs from the cloud API and alert on failed PIN attempts exceeding a configurable threshold per serial number.
Correlate failed authentication bursts with subsequent successful logins to identify likely brute-force outcomes.
Baseline normal user authentication patterns and flag deviations such as geographic anomalies or non-human request cadences.

Monitoring Recommendations

Forward API access logs to a centralized logging or SIEM platform with retention sufficient for incident investigation.
Monitor for new or unrecognized client IP addresses authenticating against registered devices.
Track post-authentication actions on each device to detect malicious configuration or command issuance.

How to Mitigate CVE-2025-46414

Immediate Actions Required

Confirm that affected accounts and devices are operating against the patched server-side service released by EG4 Electronics on April 6, 2025.
Review historical authentication logs for evidence of prior brute-force activity against device serial numbers.
Rotate PINs on any device that exhibited suspicious authentication patterns before the server-side fix was deployed.
Contact EG4 Electronics via the EG4 Electronics Contact Page for guidance on impacted deployments.

Patch Information

The vendor remediated CVE-2025-46414 through a server-side update applied on April 6, 2025. Because the fix was deployed in the cloud authentication service, customers are not required to install firmware or client updates to receive the mitigation. Refer to CISA ICS Advisory ICSA-25-219-07 for the authoritative remediation statement.

Workarounds

Treat device serial numbers as sensitive identifiers and avoid public disclosure or photography that exposes them.
Choose PINs with maximum supported length and entropy where the product allows configurable values.
Restrict outbound network exposure of administrative interfaces where the product architecture permits.
Monitor vendor advisories and apply any follow-up updates without delay.

bash

# Example: search authentication logs for repeated PIN failures per serial number
grep "PIN_AUTH_FAIL" /var/log/eg4-api/auth.log \
  | awk '{print $5}' \
  | sort | uniq -c | sort -rn | head -20