CVE-2011-4061 in db2
Summary
by MITRE
Multiple untrusted search path vulnerabilities in (1) db2rspgn and (2) kbbacf1 in IBM DB2 Express Edition 9.7, as used in the IBM Tivoli Monitoring for Databases: DB2 Agent, allow local users to gain privileges via a Trojan horse libkbb.so in the current working directory, related to the DT_RPATH ELF header.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 01/05/2025
The vulnerability CVE-2011-4061 represents a critical untrusted search path issue affecting IBM DB2 Express Edition 9.7 and the associated IBM Tivoli Monitoring for Databases: DB2 Agent components. This flaw manifests in two distinct executables db2rspgn and kbbacf1 which are susceptible to privilege escalation attacks through malicious library injection. The vulnerability stems from improper handling of dynamic library loading mechanisms within the ELF binary format, specifically involving the DT_RPATH header attribute that controls library search paths. When these executables execute with elevated privileges, they traverse the current working directory in their library search order, creating an exploitable condition where malicious actors can place crafted shared objects in the execution path.
The technical implementation of this vulnerability aligns with CWE-426, which describes untrusted search path vulnerabilities where programs execute with elevated privileges and search for libraries in insecure locations. The DT_RPATH mechanism in ELF binaries allows developers to specify additional library search paths, but when these paths include the current working directory or are otherwise improperly configured, they create opportunities for attackers to inject malicious code. In this case, the db2rspgn and kbbacf1 executables are designed to run with elevated privileges, making them attractive targets for privilege escalation attacks. The vulnerability specifically exploits the order of library resolution where the current working directory is checked before system library paths, enabling attackers to place a malicious libkbb.so file that will be loaded instead of the legitimate library.
The operational impact of this vulnerability extends beyond simple privilege escalation to encompass potential system compromise and data exposure within database environments. Local users who can write to the current working directory of these executables can effectively gain elevated privileges, potentially allowing them to execute arbitrary code with the permissions of the DB2 service account. This creates a significant risk for database administrators who may inadvertently run these processes with elevated privileges, particularly in environments where multiple users share the same system or where privilege separation is not properly enforced. The attack vector is particularly concerning because it requires minimal privileges to exploit, as the attacker only needs write access to the current working directory of the vulnerable executables rather than direct system access. The vulnerability affects database monitoring agents that are typically deployed with high privileges to ensure proper monitoring functionality, but this privilege model becomes a security risk when combined with insecure library loading practices.
Mitigation strategies for CVE-2011-4061 should focus on both immediate remediation and long-term architectural improvements to prevent similar vulnerabilities. Organizations should ensure that the affected IBM DB2 Express Edition 9.7 installations are patched with the latest security updates from IBM, as this vulnerability was addressed through proper library loading mechanisms and removal of insecure search path configurations. System administrators should implement strict file permissions and directory access controls to prevent unauthorized write access to directories where these executables operate, particularly the current working directories from which they are launched. The principle of least privilege should be enforced by ensuring that these executables run with minimal required privileges rather than elevated permissions. Additionally, security monitoring should include detection of suspicious library loading patterns and unauthorized modifications to library files in system directories. This vulnerability demonstrates the importance of secure coding practices and proper library management, aligning with ATT&CK technique T1068 which covers privilege escalation through insecure library loading, and reinforces the need for comprehensive security awareness in database administration environments. Organizations should also consider implementing application whitelisting solutions that prevent execution of unauthorized binaries and monitor for anomalous behavior in database agent processes.