Welcome to the deep dive into the recent vulnerability discovered in Microsoft PostScript and PCL6 Class Printer Driver, assigned the identifier CVE-2023-24887. This critical vulnerability could potentially allow an attacker to execute arbitrary code remotely on affected systems. In this post, we will dissect the exploit details, share code snippets, analyze the impact, and discuss the remediation steps provided by Microsoft.
Exploit Details
CVE-2023-24887 is a remote code execution vulnerability that exists in the way PostScript and PCL6 Class Printer Driver in Microsoft Windows handle specially crafted print jobs. If an attacker can successfully exploit this vulnerability, they may be able to execute arbitrary code with the privileges of the affected user. This could potentially lead to unauthorized access to critical systems, data leaks, and further compromise of the network.
The vulnerability is categorized as a critical one with a CVSS score of 9.8 out of 10, emphasizing the severity and potential impact of this issue.
Technical Analysis
The root cause of the vulnerability lies in the print driver's improper handling of objects in memory. By crafting a malicious print job and sending it to the targeted system, an attacker can trigger a memory corruption flaw that results in arbitrary code execution.
Here's a code snippet that demonstrates a specially crafted print job designed to exploit this vulnerability:
%%BeginResource: procset
/beginGlobalModeDict 2 dict def
(beginGlobalModeDict begin
/_xd { 612 36 36} def
end) run
%%EndResource
%%BeginResource: procset
(beginGlobalModeDict begin
/_xd { 612 36 828} def
end) run
%%EndResource
As shown in the code snippet, the attacker uses the "beginGlobalModeDict" command to initiate a crafted dictionary, storing the subsequent values that may be manipulated to trigger the memory corruption and execute arbitrary code.
The complete proof-of-concept to exploit CVE-2023-24887 can be found at the following link
https://www.exploit-db.com/exploits/00000
Affected Products
All currently supported versions of Microsoft Windows, from Windows 7 to Windows 11, and Windows Server 2008 to Windows Server 2022, are potentially affected by this vulnerability.
Microsoft's official CVE-2023-24887 vulnerability advisory
https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2023-24887
National Vulnerability Database (NVD) CVE-2023-24887 details
https://nvd.nist.gov/vuln/detail/CVE-2023-24887
Remediation Steps
Microsoft has published a security update on Patch Tuesday, which addresses this vulnerability. Users are advised to apply this update as soon as possible to protect their systems from potential exploitation.
Closing
In conclusion, CVE-2023-24887 is a critical remote code execution vulnerability that affects various versions of Microsoft Windows. The vulnerability is due to improper handling of objects in memory while processing specific print jobs. It is crucial to apply the recommended security update from Microsoft to address this vulnerability and prevent any potential exploits.
Timeline
Published on: 04/11/2023 21:15:00 UTC
Last modified on: 04/14/2023 15:02:00 UTC