CVE-2024-23566: HCL Aftermarket EPC Auth Bypass Flaw

CVE-2024-23566 Overview

CVE-2024-23566 affects HCL Aftermarket EPC, which lacks a CAPTCHA control on its authentication interface. The absence of an anti-automation mechanism allows attackers to submit unlimited authentication attempts against the login endpoint. This condition enables credential brute forcing, automated attacks, and account enumeration against exposed instances.

The issue is categorized under [CWE-804]: Missing CAPTCHA. Attackers can exploit the flaw over the network without prior authentication or user interaction. Successful exploitation can lead to unauthorized access when weak or reused credentials exist on valid accounts.

Critical Impact
Attackers can automate high-volume credential guessing attacks against HCL Aftermarket EPC login endpoints, enabling account takeover and user enumeration without triggering built-in anti-automation controls.

Affected Products

HCL Aftermarket EPC

Discovery Timeline

2026-07-17 - CVE-2024-23566 published to NVD
2026-07-17 - Last updated in NVD database

Technical Details for CVE-2024-23566

Vulnerability Analysis

HCL Aftermarket EPC exposes an authentication endpoint that accepts credential submissions without applying anti-automation controls. The application does not implement CAPTCHA, rate limiting, or lockout mechanisms sufficient to distinguish human logins from automated tooling. This design gap allows an unauthenticated attacker to iterate through large credential dictionaries at machine speed.

The classification under [CWE-804] (Missing CAPTCHA for Critical Function) captures the root deficiency. Because the authentication function is critical and reachable over the network, the missing control directly enables credential-based attacks. The impact extends beyond password guessing to username enumeration when server responses differ between valid and invalid accounts.

Root Cause

The root cause is the omission of a Turing-test control on the login workflow. Without CAPTCHA or an equivalent challenge, the server cannot filter automated requests from legitimate user activity. Compensating controls such as adaptive lockout, IP reputation checks, or multi-factor authentication are also insufficient to block scripted attempts against exposed instances.

Attack Vector

An unauthenticated attacker submits repeated HTTP POST requests to the HCL Aftermarket EPC login endpoint using automated tooling such as Hydra, Burp Intruder, or custom scripts. Attackers iterate through username and password lists to identify valid combinations. Differential responses in the authentication reply may also allow enumeration of valid usernames, which narrows subsequent password-guessing attempts.

Refer to the HCL Software Knowledge Base Article for vendor-published technical details.

Detection Methods for CVE-2024-23566

Indicators of Compromise

High volume of HTTP POST requests to the HCL Aftermarket EPC authentication endpoint from a single source IP or narrow IP range within a short time window.
Elevated ratio of failed logon events to successful logons in application and web server logs.
Sequential or dictionary-ordered username submissions consistent with enumeration tooling.
User-Agent strings associated with brute force utilities such as hydra, medusa, or generic scripting libraries.

Detection Strategies

Alert on authentication failure counts exceeding a defined threshold per source IP, username, or session within a rolling time window.
Correlate failed authentication events with successful logins from the same source to identify credential stuffing outcomes.
Monitor for authentication requests originating from anonymizing infrastructure, hosting providers, or known bad reputation ranges.

Monitoring Recommendations

Forward HCL Aftermarket EPC application logs and reverse proxy logs to a centralized SIEM for correlation.
Track baseline login rates per account and per source to detect statistical anomalies.
Enable alerting on account lockout spikes, which often precede or accompany brute force campaigns.

How to Mitigate CVE-2024-23566

Immediate Actions Required

Apply the vendor guidance published in the HCL Software Knowledge Base Article.
Restrict access to the HCL Aftermarket EPC login interface via network segmentation, VPN, or IP allowlisting where feasible.
Enforce strong password policies and enable multi-factor authentication for all accounts.
Review authentication logs for evidence of prior brute force or enumeration activity.

Patch Information

HCL has published remediation guidance in knowledge base article KB0132294. Administrators should review the article for the current recommended version and configuration changes. Apply vendor-supplied updates in a change-controlled maintenance window.

Workarounds

Deploy a Web Application Firewall (WAF) in front of HCL Aftermarket EPC to enforce rate limiting and challenge-response controls on the login endpoint.
Configure account lockout policies that trigger after a small number of failed authentication attempts per user.
Implement IP-based throttling at the reverse proxy layer to cap request rates against the authentication URL.
Enable geolocation filtering to block regions that do not require legitimate access to the application.

bash

# Example NGINX rate-limit configuration for the login endpoint
limit_req_zone $binary_remote_addr zone=login_zone:10m rate=5r/m;

server {
    location /login {
        limit_req zone=login_zone burst=3 nodelay;
        proxy_pass http://aftermarket_epc_backend;
    }
}