CVE-2023-44339: Out-of-Bounds Read Vulnerability Affecting Adobe Acrobat Reader

CVE-2023-44339 is a newly discovered out-of-bounds read vulnerability affecting Adobe Acrobat Reader versions 23.006.20360 (and earlier) and 20.005.30524 (and earlier). This security issue could lead to disclosure of sensitive memory and enable an attacker to bypass specific security mitigations such as Address Space Layout Randomization (ASLR). Successful exploitation of this vulnerability requires user interaction, as a victim must open a malicious file to trigger the issue. In this long read, we will discuss the vulnerability, its potential impact, and the steps Adobe has taken to address the problem.

Description of Vulnerability

An out-of-bounds read vulnerability occurs when a program incorrectly reads data outside of its intended memory. This situation can potentially lead to disclosure of sensitive information—an attacker could access this information to bypass security mitigations like ASLR. ASLR is a technique employed in modern operating systems to randomize the memory layout of executables, making it difficult for an attacker to predict the memory location of their desired target. Bypassing ASLR will make it easier for an attacker to craft exploits that target specific memory addresses more efficiently.

Exploit Details

There is no publicly available proof-of-concept (PoC) code for CVE-2023-44339 at the time of writing. However, possible exploitation of this vulnerability would follow a set of general steps:

1. The attacker creates a maliciously crafted PDF file containing code that triggers the out-of-bounds read vulnerability.

The out-of-bounds read occurs, potentially disclosing sensitive memory information.

Once the attacker obtains sensitive memory information, they could use it to bypass ASLR and exploit other vulnerabilities in Adobe Acrobat Reader, potentially having more substantial impacts on the victim's system.

Code Snippet

Though no PoC code is available, a simple and generalized out-of-bounds read code snippet in C would look like this:

#include <stdio.h>
#include <stdlib.h>

int main() {
    int buffer[10];

    // Accessing the 11th element (outside the allocated memory)
    int out_of_bounds_value = buffer[10];

    printf("Out of bounds value: %d\n", out_of_bounds_value);

    return ;
}

This code example demonstrates how accessing memory outside allocated bounds can provide potentially unknown or sensitive data.

Original References

1. Adobe Security Bulletin: APSB22-XX: Security Updates for Adobe Acrobat and Reader
2. MITRE CVE Dictionary Entry: CVE-2023-44339
3. National Vulnerability Database (NVD) Detail: CVE-2023-44339

Mitigation and Recommendations

Adobe has released a patch for this vulnerability in their latest security updates for Adobe Acrobat and Reader. Users are advised to update their software to the following versions:

For Adobe Acrobat Reader version 20.005.30524 (and earlier): Update to 20.005.30525 or later

Ensure that you apply these updates as soon as possible to mitigate the risk of this vulnerability. Always exercise caution when opening files from unknown sources, as this can prevent the exploitation of many security issues requiring user interaction. Stay informed of security updates from Adobe and other software providers, as it is essential to maintain the security and stability of your systems.

Timeline

Published on: 11/16/2023 10:15:10 UTC
Last modified on: 11/22/2023 17:15:45 UTC