CVE-2022-22389: IBM Db2 Denial of Service Vulnerability

CVE-2022-22389 Overview

CVE-2022-22389 is a denial-of-service vulnerability affecting IBM Db2 for Linux, UNIX, and Windows. The flaw exists in versions 9.7, 10.1, 10.5, 11.1, and 11.5. An authenticated attacker can submit specially crafted SQL statements that cause the database server to terminate abnormally. The vulnerability is tracked as IBM X-Force ID 221970 and is classified under [CWE-89] (SQL Injection-related input handling). Because Db2 underpins transactional and analytical workloads, an abnormal server termination can disrupt dependent applications across an enterprise.

Critical Impact
An authenticated user with low privileges can crash the Db2 instance remotely over the network, producing high availability impact on hosted databases and any application that depends on them.

Affected Products

IBM Db2 for Linux, UNIX and Windows 9.7, 10.1, 10.5, 11.1, 11.5
Linux kernel-based deployments running affected Db2 versions
Microsoft Windows and Open Group UNIX deployments running affected Db2 versions

Discovery Timeline

2022-06-24 - CVE-2022-22389 published to the National Vulnerability Database (NVD)
2024-11-21 - Last updated in NVD database

Technical Details for CVE-2022-22389

Vulnerability Analysis

The vulnerability resides in the SQL statement processing path of the Db2 engine. When the server parses or executes a specially crafted SQL statement, it encounters an unhandled error condition that causes the database process to terminate abnormally. Exploitation requires authentication, but only low privileges — any account permitted to submit SQL queries qualifies. The attack is conducted remotely over the network using the standard Db2 client protocol. Confidentiality and integrity are not impacted; the consequence is loss of database availability until the instance is restarted.

Root Cause

The root cause is improper handling of malformed or unexpected SQL input by the Db2 server process. The CWE-89 mapping reflects deficiencies in SQL input handling, though in this case the input does not result in injection but instead reaches code paths that fail to validate or sanitize inputs before processing. The unhandled condition propagates to a fatal error, terminating the server.

Attack Vector

An authenticated attacker connects to Db2 over the network using valid credentials. The attacker submits a crafted SQL statement to the server. The server fails to handle the input safely and terminates. No user interaction is required, and the attack complexity is low. Repeated submission of the malicious statement after restart can sustain a denial-of-service condition. Refer to the IBM Support Article #6598047 and IBM X-Force Vulnerability #221970 for vendor technical detail.

No verified proof-of-concept code is publicly available for CVE-2022-22389.
Refer to the IBM advisory for vendor-supplied technical details.

Detection Methods for CVE-2022-22389

Indicators of Compromise

Unexpected db2sysc process termination events in Db2 diagnostic logs (db2diag.log) without administrative initiation
Repeated client disconnects correlated with FODC (First Occurrence Data Capture) dumps generated by the Db2 instance
Authenticated SQL sessions originating from unusual source addresses immediately preceding instance crashes

Detection Strategies

Monitor db2diag.log for abnormal termination entries, signal-based crashes, and FODC trap directories created in proximity to user SQL activity
Correlate Db2 audit facility output with operating system process exit events to identify the SQL session preceding a crash
Alert on a pattern of one Db2 user account triggering multiple instance restarts within a short window

Monitoring Recommendations

Enable the Db2 audit facility (db2audit) to capture executed SQL statements and the authorization IDs that submitted them
Forward Db2 diagnostic and audit logs to a centralized SIEM or data lake for retention and correlation across hosts
Track instance uptime and automated restart counts as availability metrics with thresholds for investigation

How to Mitigate CVE-2022-22389

Immediate Actions Required

Apply the IBM-supplied fix pack or special build referenced in the IBM Support Article #6598047 for the affected Db2 version
Review Db2 user accounts and revoke SQL execution privileges from accounts that do not require them
Restrict network access to the Db2 listener port to known application hosts and administrative jump boxes

Patch Information

IBM has released remediation guidance for affected versions 9.7, 10.1, 10.5, 11.1, and 11.5. Administrators should consult the IBM Support Article #6598047 for version-specific fix packs and apply them through standard Db2 update procedures. NetApp customers integrating Db2 should also review the NetApp Security Advisory NTAP-20220729-0007.

Workarounds

Limit Db2 access to authenticated users on trusted network segments using host-based firewalls and db2set communication parameters
Reduce SQL privileges to the minimum required, and remove CONNECT authority from unused or shared accounts
Configure automated restart monitoring so that an abnormally terminated db2sysc process recovers quickly while alerts are generated

bash

# Example: restrict Db2 user privileges and enable audit logging
db2 REVOKE CONNECT ON DATABASE FROM USER suspicious_user
db2audit configure scope execute status both
db2audit start