CVE-2023-44338 - Out-of-Bounds Read Vulnerability Found in Adobe Acrobat Reader Versions 23.006.20360 and Earlier, As Well As 20.005.30524 and Earlier

The popular Adobe Acrobat Reader software application (version 23.006.20360 and earlier, as well as version 20.005.30524 and earlier) has been found to have a significant vulnerability - CVE-2023-44338. In this post, we will examine the specific cause of this vulnerability, how a malicious attacker could exploit it, and the various steps users can take to defend themselves against a potential attack.

Details of the Vulnerability

Adobe Acrobat Reader is susceptible to an out-of-bounds read vulnerability when parsing a maliciously crafted file. This flaw can result in a read past the end of an allocated memory structure, potentially allowing an attacker to execute code in the context of the current user.

To exploit this vulnerability, an attacker would need to convince a victim to open a specially crafted file with a vulnerable version of Adobe Acrobat Reader. Once the victim opens the file, the attacker may be able to execute malicious code, which could compromise the victim's system.

Pseudo-code example

1. Open crafted_file.pdf in AdobeReader(version)
2. Read-file
3. ...
   if memory_bound violated:
   4. execute attacker_code

`

In the above example, a crafted PDF file is opened in Adobe Reader, which then triggers the out-of-bounds read vulnerability. If the memory bound violation occurs, the attacker's malicious code is executed.

Original References

For more information on this vulnerability, including technical details, potential impacts, and mitigation strategies, consult the following sources:

- Adobe Security Bulletin: https://helpx.adobe.com/security/products/acrobat/apsb21-##.html
- CVE Details: https://www.cvedetails.com/cve/CVE-2023-44338/
- National Vulnerability Database: https://nvd.nist.gov/vuln/detail/CVE-2023-44338

Exploit Details

As of now, there have been no known cases of this vulnerability being actively exploited in the wild. However, given the widespread use of Adobe Acrobat Reader and the potential for critical impacts, users should not delay in implementing any available patches to mitigate the risk of exploitation.

Craft a malicious file (e.g., a PDF document) that will trigger the out-of-bounds read vulnerability

3. Socially engineer the victim to download and open the malicious PDF file using the vulnerable Adobe Acrobat Reader

Mitigation Strategies

Adobe has already released updates to address this vulnerability. It is recommended that users of Adobe Acrobat Reader promptly update their software to the latest version.

1. Update Adobe Acrobat Reader: Download and install the latest version of Adobe Acrobat Reader from Adobe’s official website
2. Be cautious when opening files from untrusted sources: Avoid opening files sent by unknown or suspicious individuals, or downloading files from unvetted websites
3. Employ proper security software: Ensure your system has updated antivirus software to detect and block potential threats

Conclusion

In short, CVE-2023-44338 is a significant vulnerability in Adobe Acrobat Reader that could allow an attacker to execute malicious code on a victim's system. Users are urged to update their software to the latest version and remain vigilant when opening files from unfamiliar sources to mitigate the risk of exploitation.

Timeline

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