CVE-2005-4870 in DB2
Summary
by MITRE
Stack-based buffer overflows in the (1) xmlvarcharfromfile, (2) xmlclobfromfile, (3) xmlfilefromvarchar, and (4) xmlfilefromclob function calls in IBM DB2 8.1 allow remote attackers to execute arbitrary code via a 94-byte second argument, which causes the return address to be overwritten with a pointer to the argument.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 08/02/2019
The vulnerability identified as CVE-2005-4870 represents a critical stack-based buffer overflow in IBM DB2 8.1 database management system. This flaw affects four specific function calls within the database engine that handle XML data processing operations. The vulnerability manifests when these functions process user-supplied input through the second argument parameter, creating a condition where an attacker can manipulate memory layout to overwrite critical program execution elements. The attack vector is particularly concerning as it enables remote code execution without requiring authentication or elevated privileges, making it a severe threat to database server integrity and system security.
The technical mechanism behind this vulnerability involves a classic stack buffer overflow scenario where the xmlvarcharfromfile, xmlclobfromfile, xmlfilefromvarchar, and xmlfilefromclob functions fail to properly validate input length before copying data to fixed-size stack buffers. When an attacker supplies a 94-byte second argument, the function's internal buffer management fails to account for the excess data, causing the stack frame to be overwritten. This overflow specifically targets the return address stored on the stack, allowing an attacker to redirect program execution flow to malicious code positioned within the supplied argument. The vulnerability aligns with CWE-121 Stack-based Buffer Overflow, which describes buffer overflow conditions where insufficient bounds checking allows data to overwrite adjacent memory locations including return addresses.
The operational impact of this vulnerability extends beyond simple code execution, as it provides attackers with complete control over the affected DB2 server. Remote attackers can leverage this vulnerability to execute arbitrary commands with the privileges of the database service account, potentially leading to data theft, system compromise, or further lateral movement within the network infrastructure. The vulnerability affects organizations running IBM DB2 8.1 in production environments where database functions are exposed to untrusted input sources, making it particularly dangerous in web applications or database interfaces that process external data without proper sanitization. This weakness creates a persistent threat that can be exploited repeatedly until patched, as the underlying buffer management flaw remains in the codebase.
Organizations should implement immediate mitigations including applying the official IBM security patches released for this vulnerability, which address the buffer overflow conditions in the affected XML processing functions. Network segmentation and access controls should be enforced to limit exposure of vulnerable database functions to untrusted networks, while input validation mechanisms should be strengthened to prevent malicious payloads from reaching the vulnerable functions. Monitoring systems should be configured to detect unusual patterns in database function calls that might indicate exploitation attempts. The vulnerability demonstrates the importance of secure coding practices in database systems and highlights the need for regular security assessments of enterprise database infrastructure to identify similar memory corruption vulnerabilities that could enable similar remote code execution capabilities. This issue also emphasizes the critical nature of maintaining up-to-date security patches in database environments, as the vulnerability was present in a widely deployed database version and could be exploited by attackers with minimal technical expertise.