CVE-2026-10747: IBM MQ Appliance RCE Vulnerability

CVE-2026-10747 Overview

CVE-2026-10747 is a pre-authentication heap buffer overflow [CWE-122] in the IBM MQ Appliance. The flaw resides in protocol message processing and can be triggered by a remote, unauthenticated attacker over the network. Successful exploitation allows an attacker to cause a denial of service or potentially execute arbitrary code on the appliance.

The vulnerability carries the maximum CVSS 3.1 base score and includes a scope change, meaning impact extends beyond the vulnerable component. Because the appliance typically brokers enterprise messaging traffic, compromise exposes downstream applications and integrations to further attack.

Critical Impact
A remote, unauthenticated attacker can execute arbitrary code or crash the IBM MQ Appliance by sending a malformed protocol message, with impact extending across trust boundaries.

Affected Products

IBM MQ Appliance (see the IBM Support Page for affected firmware versions)

Discovery Timeline

2026-09-18 - CVE-2026-10747 published to NVD
2026-09-21 - Last updated in NVD database

Technical Details for CVE-2026-10747

Vulnerability Analysis

The vulnerability is a heap-based buffer overflow in the IBM MQ Appliance protocol message parser. The flaw is reachable before authentication, so an attacker only needs network access to the MQ listener to trigger it. Exploitation can corrupt heap metadata or adjacent objects, leading to process crash or controlled memory corruption.

A scope change indicates the vulnerable component can affect resources beyond its own security authority. On a messaging appliance, this can translate to disruption of every queue manager, channel, and connected application relying on the device. Confidentiality, integrity, and availability are all impacted at the highest level.

IBM's advisory is the authoritative source for affected firmware versions and fixed releases. Refer to the IBM Support Page for the vendor's technical bulletin.

Root Cause

The root cause is improper validation of size or length fields during protocol message parsing on the heap. When an attacker-supplied message contains crafted fields, the parser writes past the bounds of a heap-allocated buffer. This overwrites adjacent heap structures used by the appliance's message handling code.

Attack Vector

The attack vector is network-based and requires no privileges or user interaction. An attacker sends a specially crafted protocol message to a network port exposed by the MQ Appliance. The malformed message triggers the overflow during pre-authentication parsing, before any credential check occurs.

No public proof-of-concept is available at time of writing, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog. Technical exploitation details are not published in the vendor advisory.

Detection Methods for CVE-2026-10747

Indicators of Compromise

Unexpected restarts, crashes, or core dumps from MQ Appliance processes handling inbound channel traffic.
Anomalous or oversized protocol messages arriving at MQ listener ports from untrusted sources.
New outbound connections initiated by the appliance to unknown destinations following inbound MQ traffic spikes.

Detection Strategies

Inspect network traffic to MQ listener ports for malformed frames, oversized length fields, or protocol-noncompliant headers.
Correlate appliance crash events with preceding inbound connections to identify potential exploitation attempts.
Compare firmware version reported by the appliance against the fixed versions listed in the IBM advisory to identify exposed systems.

Monitoring Recommendations

Forward MQ Appliance system logs, error logs, and FDC (First Failure Data Capture) events to a centralized SIEM for continuous review.
Alert on repeated TCP resets, connection anomalies, or authentication failures on MQ ports from the same source.
Monitor egress traffic from appliance management interfaces for signs of post-exploitation command and control.

How to Mitigate CVE-2026-10747

Immediate Actions Required

Apply the firmware update referenced in the IBM security bulletin as the primary remediation.
Restrict network access to MQ Appliance listener and administrative ports to trusted client subnets only.
Inventory all IBM MQ Appliance deployments and verify firmware versions against the vendor's fixed release list.

Patch Information

IBM has published remediation guidance on the IBM Support Page. Administrators should consult the bulletin for the exact fixed firmware versions applicable to their appliance model and apply the update through standard IBM MQ Appliance firmware upgrade procedures.

Workarounds

Place the MQ Appliance behind a network segmentation boundary that allows only authenticated, known client IP ranges to reach listener ports.
Terminate MQ channels through a hardened intermediary such as a channel security exit or reverse proxy where feasible.
Disable or block any unused MQ listeners and administrative services to reduce the pre-authentication attack surface.