CVE-2022-34312 is a security vulnerability found in IBM CICS Transaction Server for Multiplatforms (CICS TX) version 11.1. This flaw allows web pages processed by the server to be stored locally, where they could be read by other users on the same machine. That’s a big deal if your system is shared or accessed by multiple people—it means private data could leak simply because it’s in an unsecured cache.

The issue was first publicized by IBM under X-Force ID 229447. In this long read, we’ll walk through exactly what the bug is, how it can be exploited step-by-step, and what you should do to mitigate the risk.

What Is IBM CICS TX and Who Uses It?

IBM CICS (Customer Information Control System) TX is a transaction processing solution often used in enterprise settings. It lets organizations build, deploy, and manage critical back-end applications, especially where a lot of users or transactions need to be handled at once.

The TX 11.1 release improved support for cloud and container environments, but the vulnerability we’re discussing today affects its web-based interaction.

Vulnerability Details

CVE: CVE-2022-34312  
IBM X-Force ID: 229447  
Product Affected: IBM CICS TX 11.1  
CVSS Score: 4.4 (Medium)  
Basic Summary: Web pages generated by the application may be stored locally on the server’s file system with permissions that permit other local users to read them.

Here’s what’s going on, step by step

1. A user accesses a web resource on the CICS system (could be a web-based admin panel, user portal, or any web app running through CICS TX).

Files are stored with world-readable permissions or in a directory accessible by all users.

4. Another user with shell access on the same system can read these files, potentially exposing sensitive data, session identifiers, or private application information.

Exploit Example (Step-by-Step)

Let’s break down an example scenario on a Linux system.

Step 1: The file save path  
Suppose CICS TX stores served pages in /var/cics/webcache.

Step 2: Default permissions

When files are saved, they might be created like this

$ ls -l /var/cics/webcache/
-rw-r--r-- 1 cicsadmin cics  4096 Jun 17 11:00 user-home.html

The permissions here (rw-r--r--) mean *any* local user can read this file.

Step 3: Attacker reads the file

Any regular user logged in (not the web user!) can do

$ cat /var/cics/webcache/user-home.html

Now, whatever sensitive data was in that page—usernames, transaction details, session cookies—are exposed.

Here’s a simplified Python simulation that demonstrates this storage risk

# Simulating file write by web server process
file_path = '/var/cics/webcache/user-home.html'
page_content = "<html>User: Alice
Session: 123456abcdef</html>"

with open(file_path, 'w') as f:
    f.write(page_content)

# Suppose file permissions are set (simulating world-readable)
import os
os.chmod(file_path, o644)

# Another user can read this:
with open(file_path, 'r') as f:
    print(f.read())

Original References

- IBM Security Bulletin: CVE-2022-34312
- CVE Details on NIST
- IBM X-Force Exchange 229447

Mitigation

1. Update IBM CICS TX as soon as possible. Check the IBM official fix.

2. Check directory permissions where web pages or other sensitive files are saved. Limit them to the application user only:

`bash

chmod -R 700 /var/cics/webcache
  chown -R cicsadmin:cics /var/cics/webcache

`

3. Review application logging and caching practices. Make sure temporary or cached information is not stored with insecure permissions.

4. Audit users with local access, and consider restricting shell access if not absolutely necessary.

Why This Matters

While this bug is “only” local, in many organizations multiple admins, contractors, or other services could have access to production systems. A misconfigured server—even briefly—could result in leaks that have compliance or privacy consequences.

Conclusion

CVE-2022-34312 is a textbook example of why secure local storage and file permissions matter, even on “trusted” systems. If you’re running IBM CICS TX 11.1, audit your configuration right now—before this simple bug becomes a bigger problem.

If you want to dig deeper, here are the official resources to get started

- IBM Security Bulletin
- NVD Entry on CVE-2022-34312
- X-Force Exchange

Stay safe, audit your permissions, and keep your critical systems locked down!

Timeline

Published on: 11/14/2022 18:15:00 UTC
Last modified on: 11/16/2022 20:24:00 UTC