Adobe Illustrator is one of the most popular vector graphics editors in the world, used by both amateurs and professionals. But, like all software, it isn’t immune to security vulnerabilities. One such vulnerability, identified as CVE-2022-23187, puts users at risk of falling victim to arbitrary code execution thanks to an underlying buffer overflow bug.

In this long-read, we'll break down what CVE-2022-23187 is, how the exploit works, the risks involved, and what you can do to protect yourself. This article is exclusive and puts everything into simple language for easy understanding.

What is CVE-2022-23187?

CVE-2022-23187 is a vulnerability affecting Adobe Illustrator version 26..3 and earlier. It’s a buffer overflow vulnerability, which means the program does not properly check the length of memory allocations when processing certain crafted files.

If an attacker convinces a user to open a specially crafted file in Illustrator, that file can cause too much data to be written to a buffer, spilling over its bounds. This overspill could be manipulated to run code with the privileges of the user who opened the file.

How the Exploit Works

The exploit relies on improper bounds-checking when Illustrator parses crafted vector graphic files (like .AI or .EPS). The file contains deliberately malformed data that Illustrator can't handle properly. When the overflow happens, the attacker can overwrite *important data* in the program’s memory—including pointers that tell Illustrator where to execute code.

Example: Buffer Overflow in C

Let’s look at a simplified C code snippet showing how this might happen at a low level (not Illustrator source code, but an analogy):

#include <stdio.h>
#include <string.h>

void parse_file(char *user_input) {
    char buffer[256];
    // The dangerous function: no bounds check!
    strcpy(buffer, user_input); 
    printf("Parsed file: %s\n", buffer);
}

int main(int argc, char *argv[]) {
    if (argc > 1) {
        parse_file(argv[1]);
    } else {
        printf("Please provide a file to parse.\n");
    }
    return ;
}

If an attacker provides a string longer than 256 characters, the code will overflow 'buffer', potentially letting them hijack program execution.

Crafting the Malicious File

Security researchers discovered that an Illustrator file (.AI) could be manipulated to include an oversized field—maybe an embedded image, path, or custom metadata. When Illustrator tries to process this field:

Example of an Artificially Crafted Malicious AI File Structure

*This is illustrative pseudo-code, not and actual exploit:*

HEADER: [Valid AI file header bytes]
MALICIOUS_FIELD: [NOP NOP NOP NOP SHELLCODE PAYLOAD]
TRAILER: [Fake data to align execution]

The attacker could use public tools to craft and test such files.

Required User Interaction

The good news—such an attack can’t happen without you. The attacker has to convince you to open the malicious file in Illustrator. They may do this by:

Proof-of-Concept Exploit

Due to responsible disclosure, we won’t show a live exploit. However, the following is a highly simplified pseudocode reference:

with open("evil.ai", "wb") as f:
    header = b"%AI5_File" + b"\x00" * 100
    overflow = b"A" * 300 + b"\xcc" * 8  # Overwrites memory past buffer
    payload = b"\x90" * 100 + b"\xeb\x10..." # NOP sled + shellcode
    f.write(header + overflow + payload)

*Note: The above “evil.ai” file is a mock-up for demonstration. Generating functional exploits is illegal outside controlled testing environments.*

References

- Adobe Security Bulletin APSB22-01
- NVD CVE-2022-23187 Entry
- Original MITRE CVE Entry

Mitigation and Protection

1. Update Illustrator:  
Adobe has released updates to patch this issue. Upgrade to the latest version from the Adobe website.

2. Be Cautious with Files:  
Never open Illustrator files from unknown or untrusted sources.

3. Use Security Tools:  
Utilize anti-malware programs and endpoint protection that can detect malicious files.

4. Educate Users:  
Train all staff about phishing and the risks of opening unknown files.

Conclusion

CVE-2022-23187 is a classic example of a buffer overflow vulnerability, allowing attackers to execute code just by tricking a victim into opening a specially crafted file. Adobe’s quick response and patch helps keep users safe, but vigilance is always necessary.

Always update your software and think twice before opening files from untrusted sources.


#### *Stay Secure! For more details, visit the official Adobe Security Bulletin.*

Timeline

Published on: 03/11/2022 18:15:00 UTC
Last modified on: 03/18/2022 13:46:00 UTC