External risk intelligence

IBM Db2 Mirror for i Authentication Bypass Vulnerability

CVE advisorySeverity: CRITICAL (CVSS 9.8)

CVE-2026-17182

IBM Db2 Mirror for i is a database replication solution designed for internal high-availability environments. While it involves network communication, it is typically restricted to internal server-to-server traffic and is not intended to be exposed to the public internet in standard deployment configurations.

Authentication Bypass

Ibm Db2 Mirror For I

7.4 to 7.6

Halo Surface Signal: 2 out of 5 — less likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

This advisory concerns a critical security vulnerability in IBM Db2 Mirror for i, a technology used for database replication. The vulnerability could allow unauthorized remote access, potentially leading to the theft or modification of sensitive information. The main concern is confirming whether this technology is in use within your environment and if it is exposed in a way that could be exploited.

Unauthorized access to sensitive data is possible.
Remember if IBM Db2 Mirror for i is deployed.
Assess exposure and relevance to business operations.

Attack Path

How an attacker could exploit the issue

An attacker could exploit this vulnerability by sending specially crafted requests to a vulnerable IBM Db2 Mirror for i system. Because the system improperly validates parts of the request's address, an unauthenticated attacker can bypass security checks. This could allow them to access or change sensitive data.

No authentication required.
Malicious request URI sent.
Unauthorized data access or modification.

Live Threat

Current exploitation, exposure, and threat context

IBM Db2 Mirror for i could allow an unauthenticated remote attacker to bypass authentication and gain unauthorized access to, or modify, sensitive information when a vulnerable URI path segment is improperly validated.

Sensitive data could be accessed or altered.
Attackers may bypass authentication mechanisms.
Unauthorized access to critical information is possible.

Operational Fix

Recommended remediation, mitigation, and detection steps

Given the nature of IBM Db2 Mirror for i, ownership likely resides with the database administrators and the platform or infrastructure teams responsible for the IBM i operating system and its core services. The initial practical move is to inventory all instances of Db2 Mirror for i, confirm their network exposure and business criticality, and identify the specific application or system owners accountable for each instance to prioritize remediation efforts.

Database and platform teams own this issue.
Verify network exposure and business criticality.
Plan remediation based on identified 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 IBM Db2 Mirror for i?

IBM Db2 Mirror for i is a database replication solution. It is used by organizations running the IBM i operating system to maintain continuous availability by keeping data synchronized across multiple servers in real-time, ensuring that critical business applications remain operational.

What does CVE-2026-17182 mean for system security?

This vulnerability is classified as an improper authentication issue (CWE-287). It means the system fails to verify the identity of a user correctly. Because of this, an attacker could bypass authentication steps entirely to interact with the database, potentially reading or changing sensitive information without needing valid credentials.

How does an attacker trigger this vulnerability?

An attacker triggers the vulnerability by sending a specially crafted network request to the system. The flaw exists because the software does not properly check the URI path segments in the request. Note that simply communicating with the system does not trigger the bug; the request must be maliciously formatted to exploit the path validation error.

Is my system at risk if it is not internet-facing?

According to Halo Surface Signal, this software is designed for internal high-availability environments and is typically restricted to server-to-server traffic. If your instances are kept within internal network segments and are not exposed to the public internet, the practical likelihood of remote exploitation is significantly lower.

How should I respond to this vulnerability?

Start by identifying all instances of Db2 Mirror for i within your infrastructure. Consult with your database administrators and platform teams to confirm if the software is running, assess whether these instances are reachable over your network, and determine their business criticality to prioritize your next steps.

References

www.ibm.com/support/pages/node/7283359

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.