Overview
The Common Vulnerabilities and Exposures (CVE) system has recently identified a significant vulnerability, designated as CVE-2025-25278, that affects OpenHarmony v5.0.3 and all prior versions. This vulnerability presents a serious threat as it allows a local attacker to execute arbitrary code in tcb via a race condition, potentially leading to system compromise or significant data leakage. This blog post aims to provide a comprehensive understanding of the vulnerability, its potential impacts, and guidance on how to mitigate its risks.
Vulnerability Summary
CVE ID: CVE-2025-25278
Severity: High (8.4/10 on CVSS Severity Score)
Attack Vector: Local
Privileges Required: Low
User Interaction: None
Impact: Potential system compromise or data leakage
Affected Products
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Product | Affected Versions
OpenHarmony | v5.0.3 and prior versions
How the Exploit Works
The vulnerability lies in the tcb of OpenHarmony. Tcb (thread control block) is a data structure in OS kernel which holds thread-specific data needed to manage the thread. The vulnerability arises due to a race condition, which is a type of flaw that occurs when the behavior of a software system depends on the sequence or timing of other uncontrollable events.
In this case, the race condition can be manipulated by a local attacker to execute arbitrary code. This means that an attacker with access to the system can exploit this vulnerability to potentially take control of the system or cause data leakage, creating a severe security risk.
Conceptual Example Code
The following is a conceptual example of how the vulnerability might be exploited. In a real-world scenario, the actual malicious payload would be specifically crafted by an attacker to exploit the target system:
$ ./exploit_program --tcb_race_condition --execute_arbitrary_codeIn this example, `exploit_program` is a hypothetical utility an attacker might use to exploit the race condition in tcb and execute arbitrary code. Note that this is a simplified representation and actual exploitation would involve more sophisticated techniques and tools.
Mitigation Guidance
The primary mitigation for this vulnerability is to apply the vendor patch. OpenHarmony has been notified about the vulnerability and they are likely to release a patch to address it. All users running a vulnerable version of OpenHarmony should apply this patch as soon as it becomes available.
In the interim, or for those unable to apply the patch immediately, a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can be used as temporary mitigation. These systems can help detect and block attempts to exploit this vulnerability. However, they are not a complete solution and should be used in conjunction with the vendor patch for optimal protection.