CVE-2024-21860: Arbitrary Code Execution Vulnerability in OpenHarmony

Overview

In the ever-evolving landscape of cybersecurity, it is crucial to stay vigilant about potential vulnerabilities. This blog post highlights a critical vulnerability, CVE-2024-21860, found in OpenHarmony v4.0.0 and earlier versions. This vulnerability could allow an adjacent attacker to execute arbitrary code in any apps due to a use-after-free issue, leading to system compromise or data leakage. This issue is of significant concern to all users and developers of OpenHarmony, as it could potentially compromise the integrity, confidentiality, and availability of their systems.

Vulnerability Summary

CVE ID: CVE-2024-21860
Severity: High (8.2)
Attack Vector: Adjacent network
Privileges Required: None
User Interaction: None
Impact: Arbitrary code execution leading to potential system compromise or data leakage

Affected Products

Product | Affected Versions

OpenHarmony | v4.0.0 and earlier versions

How the Exploit Works

The core of the vulnerability lies in the use-after-free issue. In OpenHarmony v4.0.0 and earlier versions, certain memory objects are released or ‘freed’ after their use. However, due to a programming error, these objects can still be accessed or ‘used’ after being freed. This flaw can be exploited by an adjacent attacker who can inject malicious code into the ‘freed’ memory space, leading to arbitrary code execution in any apps.

Conceptual Example Code

While the specifics of the exploit would vary based on the application and the attacker’s intent, a conceptual example might look something like this:

// Memory is allocated
char *buffer = (char*) malloc(sizeof(char) * 100);
// Memory is used
strcpy(buffer, "sensitive data");
// Memory is freed
free(buffer);
// Memory is used after being freed (vulnerable)
strcpy(buffer, "malicious code");

In this example, even though the memory has been freed, it is still being used to store new data. An attacker could exploit this by writing malicious code into the freed memory space, leading to arbitrary code execution.

Mitigation Guidance

To mitigate this vulnerability, users should apply the vendor-provided patch as soon as possible. In cases where immediate patching is not feasible, using a Web Application Firewall (WAF) or an Intrusion Detection System (IDS) can serve as a temporary mitigation strategy. These tools can monitor network traffic and detect potential exploit attempts, providing an additional layer of security. However, these are not permanent solutions and do not eliminate the underlying vulnerability. Therefore, applying the patch remains the most effective mitigation strategy.