CVE-2024-43189: IBM Concert Information Disclosure Flaw

CVE-2024-43189 Overview

IBM Concert Software versions 1.0.0 through 1.0.1 fail to properly enable HTTP Strict Transport Security (HSTS). This weakness allows a remote attacker positioned between the client and server to downgrade connections and intercept sensitive data. The flaw is classified under CWE-327: Use of a Broken or Risky Cryptographic Algorithm because the transport layer does not enforce continuous TLS usage. Exploitation requires a man-in-the-middle (MITM) position on the network path, which raises attack complexity but does not require authentication or user interaction.

Critical Impact
An attacker with network positioning can strip TLS and capture credentials, session tokens, or other sensitive data exchanged with IBM Concert.

Affected Products

IBM Concert Software 1.0.0
IBM Concert Software 1.0.1
Deployments exposing the Concert web interface without external HSTS enforcement

Discovery Timeline

2024-11-15 - CVE-2024-43189 published to the National Vulnerability Database
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2024-43189

Vulnerability Analysis

IBM Concert Software does not emit the Strict-Transport-Security response header on HTTPS responses. Without HSTS, browsers do not remember to enforce TLS for subsequent requests to the host. An attacker on the same network segment can intercept the initial plaintext HTTP request and prevent the upgrade to HTTPS. This enables a classic SSL-stripping attack where the victim communicates with the attacker over HTTP while the attacker relays traffic to Concert over HTTPS.

Because the exploitation window depends on an attacker holding a privileged network position, the issue is scored with high attack complexity. However, the confidentiality impact is significant when successful, since Concert handles application governance and compliance data.

Root Cause

The root cause is a missing security response header in the web server configuration shipped with IBM Concert 1.0.0 and 1.0.1. HSTS instructs conformant browsers to only connect to a host over TLS for a specified duration. Its absence leaves the first request, and any subsequent user-typed URL, vulnerable to protocol downgrade.

Attack Vector

An attacker must be positioned on the network path between a Concert user and the server. Common scenarios include compromised Wi-Fi, ARP spoofing on shared LAN segments, or upstream router compromise. The attacker intercepts the plaintext HTTP request that precedes an HTTPS upgrade, proxies the session, and captures credentials or session cookies transmitted by the browser. See the IBM Support Document for vendor-specific technical details.

Detection Methods for CVE-2024-43189

Indicators of Compromise

Unexpected HTTP (port 80) traffic to Concert hostnames that normally serve HTTPS
Session cookies for Concert appearing in cleartext captures from network sensors
Authentication anomalies in Concert audit logs originating from unexpected source IPs

Detection Strategies

Inspect HTTPS responses from Concert endpoints and confirm whether a Strict-Transport-Security header is returned; its absence confirms exposure.
Deploy network detection rules for SSL-stripping behavior, such as clients sending credentials over HTTP to hosts that should be HTTPS-only.
Correlate browser telemetry with proxy logs to identify sessions that failed to upgrade to TLS.

Monitoring Recommendations

Monitor egress and internal traffic for plaintext requests to Concert URLs and alert on any occurrence.
Track TLS handshake failures and downgrade events against Concert servers using network detection tooling.
Review authentication logs for logins from geographies or ASNs inconsistent with the user population.

How to Mitigate CVE-2024-43189

Immediate Actions Required

Apply the fix referenced in the IBM Support Document for IBM Concert 1.0.0 and 1.0.1.
Place Concert behind a reverse proxy or load balancer that injects a strict Strict-Transport-Security header until patching completes.
Restrict Concert web access to trusted network segments or VPN-only pathways to reduce MITM exposure.

Patch Information

IBM has published remediation guidance in the IBM Support Document for CVE-2024-43189. Administrators should upgrade to the fixed release identified by IBM and validate that HSTS is returned on all HTTPS responses after the upgrade.

Workarounds

Configure an upstream proxy (NGINX, Apache, F5, or similar) to add Strict-Transport-Security: max-age=31536000; includeSubDomains on all Concert responses.
Preload the Concert hostname into the browser HSTS preload list for organization-managed browsers via group policy.
Enforce HTTPS-only navigation policies in enterprise browsers and disable insecure fallback for Concert domains.

bash

# Example NGINX reverse proxy snippet to enforce HSTS in front of IBM Concert
server {
    listen 443 ssl http2;
    server_name concert.example.com;

    add_header Strict-Transport-Security "max-age=31536000; includeSubDomains" always;

    location / {
        proxy_pass https://concert-backend.internal;
        proxy_set_header Host $host;
        proxy_set_header X-Forwarded-Proto https;
    }
}