CVE-2025-1329: Local User Arbitrary Code Execution Vulnerability in IBM CICS TX

Overview

A critical security vulnerability has been discovered in IBM CICS TX Standard 11.1 and IBM CICS TX Advanced 10.1 and 11.1. This vulnerability, designated as CVE-2025-1329, could potentially allow a local user to execute arbitrary code on the system. This is due to a failure in the handling of DNS return requests by the gethostbyaddr function.
The impact of this vulnerability is significant and can lead to potential system compromise or data leakage. Therefore, it is crucial for users and administrators of the affected systems to apply necessary security measures and mitigations as soon as possible.

Vulnerability Summary

CVE ID: CVE-2025-1329
Severity: High (CVSS: 7.8)
Attack Vector: Local
Privileges Required: Low
User Interaction: None
Impact: System compromise and potential data leakage

Affected Products

Product | Affected Versions

IBM CICS TX Standard | 11.1
IBM CICS TX Advanced | 10.1, 11.1

How the Exploit Works

The exploit works by taking advantage of a flaw in the gethostbyaddr function in IBM CICS TX. This function is supposed to safely handle DNS return requests. However, due to a failure in this function, a local user can manipulate the returned DNS data to inject and execute arbitrary code on the system. This could lead to unauthorized access, data manipulation or even total system compromise.

Conceptual Example Code

Here is a conceptual example of how the vulnerability might be exploited:

#include <netdb.h>
#include <stdio.h>
int main() {
struct hostent *host_entry;
char *malicious_payload = "Injected malicious code";
host_entry = gethostbyaddr(malicious_payload, sizeof(malicious_payload), AF_INET);
if(host_entry == NULL) {
printf("Exploit failed.\n");
return 1;
}
printf("Exploit successful. Executing malicious code.\n");
system(malicious_payload);
return 0;
}

This example represents a C program that a malicious user could use to exploit the gethostbyaddr vulnerability. By inserting a malicious payload into the function, they could potentially execute arbitrary code on the system.
Please note that this is a conceptual example and should not be used for malicious purposes. It’s important to apply the vendor patch or utilize WAF/IDS for temporary mitigation to protect your systems from this vulnerability.