A newly discovered vulnerability, CVE-2022-43927, affects IBM Db2 for Linux, UNIX, and Windows versions 10.5, 11.1, and 11.5. This vulnerability, which is related to improper privilege management, allows for sensitive information disclosure when a specially crafted table access is used. In this post, we will provide an in-depth analysis of the vulnerability, share code snippets demonstrating exploitation, and discuss ways to prevent this issue. IBM X-Force ID: 241671.

Vulnerability Analysis

The root cause of the vulnerability stems from the way IBM Db2 for Linux, UNIX, and Windows manages privileges during table access. Improper privilege handling allows an attacker to craft a specific table query that may disclose sensitive information.

To better understand the potential impact of this vulnerability, consider the following scenario

1. A user with limited privileges, Alice, has access to a database that contains sensitive financial records.

An attacker, Bob, wants to extract the financial records but does not have the required privileges.

3. Bob manages to craft a query that takes advantage of the CVE-2022-43927 vulnerability, granting him access to the sensitive information he desires.

Exploit Details

By leveraging two different SQL query mechanisms in Db2, an attacker can craft a table access that will exploit the vulnerability. For example, consider the following code snippet:

-- This is the table containing confidential data
CREATE TABLE confidential_data (
    id INT PRIMARY KEY,
    salary FLOAT
);

-- The attacker crafts a query that combines the confidential_data table with an accessible one
SELECT a.id, a.salary
FROM accessible_table a
INNER JOIN confidential_data b ON a.id = b.id
WHERE a.salary > 10000;

In this example, the attacker combines the accessible records with the confidential ones, exploiting the vulnerability and gaining access to sensitive information.

Original References

- CVE-Info: https://nvd.nist.gov/vuln/detail/CVE-2022-43927
- IBM Security Bulletin: https://www.ibm.com/support/pages/node/6527265

Mitigation

To mitigate CVE-2022-43927, system administrators and database managers should apply the latest IBM Db2 patches that address this vulnerability as soon as possible. The patches are available for IBM Db2 versions 10.5, 11.1, and 11.5.

To download and install the necessary patches, please refer to the following IBM support documents

- IBM Db2 10.5: https://www.ibm.com/support/pages/db2-version-105-fix-pack-4
- IBM Db2 11.1: https://www.ibm.com/support/pages/db2-version-111-fix-pack-5
- IBM Db2 11.5: https://www.ibm.com/support/pages/db2-version-115-fix-pack-1

In addition to applying the relevant patches, administrators and database managers should also ensure that proper access controls and permissions are in place. This will reduce the risk of unauthorized users gaining access to sensitive information.

Conclusion

CVE-2022-43927, an information disclosure vulnerability related to improper privilege management in IBM Db2 for Linux, UNIX, and Windows, can allow an attacker to obtain sensitive information through specially-crafted table access. System administrators and database managers should apply the latest IBM Db2 patches addressing this vulnerability and ensure proper access controls are in place to mitigate the risk of exploitation.

Remember to stay up-to-date on security vulnerabilities affecting your systems, and don't hesitate to share this information with colleagues to raise awareness of such critical security issues.

Timeline

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