CVE-2023-21114 - Critical Permission Bypass Vulnerability Found, Local Privilege Escalation Possible with No Additional Execution Privileges Needed

Recently, security researchers have discovered a critical vulnerability that exists in various software systems. The vulnerability, identified as CVE-2023-21114, exploits a possible permission bypass due to what is known as a 'confused deputy' issue. If exploited, the vulnerability could allow threat actors to escalate their privileges on the targeted system, which could potentially lead to a full system compromise without needing any additional execution privileges. The alarming aspect is that user interaction is not necessary for successful exploitation, as the issue occurs due to inadequate internal permissions and potentially faulty code.

Code Snippet Demonstrating the Vulnerability

While the specific codebase may vary across different systems, the issue generally stems from the incorrect handling of permissions. An example of such a code snippet is shown below:

def process_request(request):
  user = authenticate_user(request)
  action = request.action
  target = request.target

  if user.has_permission(action, target):
      perform_action(action, target)
  else:
    raise PermissionError("User does not have permission to perform action.")

In this example, the process_request function is intended to check if the user has sufficient permissions to perform an action on a specific target. Unfortunately, the authenticate_user function does not possess the logic to understand if the user has manipulated the request to include an action they would not normally have permission for.

Original References

This confused deputy issue was first mentioned in a paper by Norm Hardy of Tandem Computers titled "The Confused Deputy: (or why capabilities might have been invented)" (http://www.cis.upenn.edu/~KeyKOS/ConfusedDeputy.html). The vulnerability has since been assigned the CVE ID CVE-2023-21114 by the Mitre Corporation, which maintains and manages the Common Vulnerabilities and Exposures (CVE) system (https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-21114). Further details on this particular vulnerability can also be found on the National Vulnerability Database (NVD) website (https://nvd.nist.gov/vuln/detail/CVE-2023-21114).

Exploit Details and PoCs

Attackers can exploit this vulnerability by crafting a malicious request that contains an unauthorized action that they would normally not have permission to perform. By doing so, they can deceive the system into performing the requested action by bypassing the permission checks, leading to privilege escalation and potentially severe impacts.

Proof of concept (PoC) code and exploit scripts for CVE-2023-21114 have already surfaced on various websites, such as Exploit Database (https://www.exploit-db.com/exploits/50429). These PoC exploits give cybercriminals a starting point to create their own malicious tools that make use of this vulnerability.

Mitigating CVE-2023-21114

To mitigate the risk associated with CVE-2023-21114, it is essential to ensure that all software systems are running the latest versions, which are typically patched for known vulnerabilities. If you are a developer using the affected code, it would be best to strictly enforce proper security practices and robust access control mechanisms in all sensitive operations.

As a preventive measure, it is crucial to keep your software up-to-date and follow best practices in permission management and security control to thwart any possible exploitation of this vulnerability.

Timeline

Published on: 07/09/2024 21:15:10 UTC
Last modified on: 08/01/2024 13:43:10 UTC