CVE-2022-28831 - Out-of-Bounds Write in Adobe InDesign—How a Simple File Can Let Hackers Take Over

Adobe InDesign is one of the most popular tools for creating professional documents, books, and mags. But like most big pieces of software, sometimes vulnerabilities sneak in. CVE-2022-28831 refers to a dangerous bug in InDesign that lets bad guys run code on your computer just by tricking you into opening the wrong file. In this long read, I’ll explain this flaw in plain English, share code snippets, and point to the sources you need for learned more.

What Is CVE-2022-28831?

CVE-2022-28831 is an out-of-bounds write vulnerability found in Adobe InDesign versions 17.1 (and prior) and 16.4.1 (and prior). An attacker can exploit this by sending a user a specifically crafted InDesign file (.INDD). If the user opens it, the software writes data to the wrong part of memory (outside the buffer), which lets hackers mess with how the program runs—potentially allowing them to execute any code they want in the context of the unwary user. This could mean installing malware, stealing data, or taking over your system.

How Does It Work? (Simple Explanation)

1. The Attacker’s Trick: They craft a malicious .INDD file with strange or overlong data inside certain fields (like objects, fonts, or colors).
2. User Interaction: You get an innocuous-looking InDesign file by email, download, or shared drive. You open it.
3. Out-of-Bounds Write: Because of the bug, InDesign writes more data than it should outside of a buffer—the section of memory assigned to hold data.
4. Arbitrary Code Execution: This "overwrite" can change how the program behaves, giving hackers control within your user account.

Technical Details and Example

The official Adobe security bulletin (see references below) is light on the gritty technicals, but out-of-bounds writes often happen in code like this (simplified C/C++ style):

void readData(char *input) {
    char buffer[100];
    strcpy(buffer, input); // Danger! No bounds checking
    // ... more processing
}

If input is longer than 100 characters, strcpy() will happily write past the edge of buffer—into whatever memory comes next—possibly overwriting important code or data.

When attackers create a malicious InDesign file, they're carefully filling certain fields with too much data, knowing that older InDesign versions will make this mistake somewhere in the code.

Exploit Example (Simulation)

Hackers usually use fuzzing tools to discover such bugs and then tailor malicious files. While there’s no public “one-click” proof-of-concept exploit available, here’s a Python pseudocode snippet to show how an attacker might generate an overlong field for exploitation:

# Malicious InDesign file generator (PSEUDO-CODE, not real INDD structure)
filename = "malicious.indd"
payload = b"A" * 500  # Overruns the field where InDesign expects less data
with open(filename, "wb") as f:
    f.write(b"%INDD_HEADER%")
    f.write(payload)
    f.write(b"%END%")

The crafted file is then sent to the victim, who trusts it's safe and opens it in InDesign. If their version is vulnerable, the out-of-bounds write happens.

Risk and Impact

- Severity: High/critical (arbitrary code execution)

User Interaction: Required (must open the bad file)

- Context: Runs as the current user, so can't break out to system privileges unless more flaws exist

How to Protect Yourself

1. Update to the latest Adobe InDesign version (Adobe security updates page).

Additional Reading and References

- NIST National Vulnerability Database entry for CVE-2022-28831
- Adobe Security Bulletin (APSB22-28)
- Summary from SecurityFocus (archived)

Conclusion

CVE-2022-28831 is proof that even pro tools like Adobe InDesign aren't immune to security bugs. Just remember: keep your software updated, don’t open random files, and always be wary of what lands in your inbox. Simple steps, but they’ll keep you much safer from attackers making the most of flaws like this one.

Stay smart—and let your creative work stay yours.

Timeline

Published on: 09/11/2023 14:15:00 UTC
Last modified on: 09/11/2023 14:26:00 UTC