CVE-2022-44520: Critical Use-After-Free Vulnerability in Acrobat Reader DC Allowing Arbitrary Code Execution

A critical use-after-free vulnerability (CVE-2022-44520) has been discovered in Acrobat Reader DC versions 22.001.20085 (and earlier), 20.005.3031x (and earlier), and 17.012.30205 (and earlier). This vulnerability could potentially allow an attacker to execute arbitrary code in the context of the currently logged-in user. To exploit this issue, an attacker would require the victim to open a specially crafted malicious file.

Important Links

- Adobe Security Bulletin
- CVE-2022-44520 Details
- Adobe Acrobat Reader DC Download

Vulnerability Details

The root cause of this vulnerability is the incorrect handling of memory objects by Adobe Acrobat Reader DC. The application releases an object but continues to use it, leading to a use-after-free condition. This scenario can be abused to execute arbitrary code under the context of the current user.

Code Snippet

The vulnerability could be exploited through a specially crafted PDF file that causes Acrobat Reader DC to release a memory object and then access it. The following is a high-level representation of the vulnerable code path:

// Example vulnerable code (high-level pseudo-code)
void process_pdf_file(char *file) {
    Object *obj = read_pdf_object(file);

    if (check_object_validity(obj)) {
        process_object(obj);
    }

    release_object(obj);

    // Later in the code, the released object is accessed
    access_after_free(obj);
}

To exploit this vulnerability, an attacker would need to develop a malicious PDF file that causes the memory object to be released prematurely but still continues the object's usage after being released.

Exploit Steps

1. The attacker creates a malicious PDF file that triggers the use-after-free condition in Acrobat Reader DC.

The victim opens the malicious PDF file using an affected version of Adobe Acrobat Reader DC.

4. The malicious code executes under the context of the current user, allowing the attacker to gain control of the victim's system.

Mitigation

Users are encouraged to update their Adobe Acrobat Reader DC installations to the latest version, which addresses this vulnerability.

- Adobe Acrobat Reader DC 22.002.20095 Update

Additionally, users should exercise caution when opening PDF files from unknown sources. Do not open PDF files from untrusted sources or click on links to PDF files in emails from unknown senders.

Conclusion

The CVE-2022-44520 vulnerability in Acrobat Reader DC is a critical security issue that could allow an attacker to execute arbitrary code on a victim's system. To protect against this vulnerability, users should update Adobe Acrobat Reader DC to the latest version and practice safe browsing habits when dealing with PDF files.

Timeline

Published on: 12/19/2024 00:15:06 UTC