CVE-2025-52458

Executive Summary

CVE-2025-52458 is a local out-of-bounds write vulnerability affecting OpenHarmony versions up to and including v5.1.0. This flaw allows a local attacker to achieve arbitrary code execution within the context of pre-installed applications. The vulnerability is classified as a memory corruption issue (CWE-787) and carries a CVSS score of 5.5 (Medium). Exploitation is restricted to scenarios where the attacker already has local access to the device, significantly limiting the attack surface. No public proof-of-concept (PoC) code or exploit is currently available, and the patch status remains unknown. The EPSS score of 0.0% indicates a very low probability of exploitation in the wild at this time.

CVSS Breakdown & Threat Level

• CVSS Score: 5.5 (Medium)
• Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
• Attack Vector (AV): Local (L) – The attacker must have physical or shell access to the device.
• Attack Complexity (AC): Low (L) – No special conditions are required beyond local access.
• Privileges Required (PR): Low (L) – The attacker needs some level of user privileges.
• User Interaction (UI): None (N) – No victim interaction is needed.
• Scope (S): Unchanged (U) – The vulnerability does not affect other components.
• Confidentiality (C): High (H) – Arbitrary code execution can lead to data theft.
• Integrity (I): High (H) – Code execution allows modification of system data.
• Availability (A): High (H) – Code execution can disrupt system operations.

Threat Level: Medium. While the impact is severe (arbitrary code execution), the requirement for local access and the restricted exploitation scenarios lower the overall risk. The lack of a public PoC and low EPSS score further reduce immediate threat.

Deep Dive & Mechanics

The vulnerability resides in the memory management of pre-installed applications within OpenHarmony. An out-of-bounds write occurs when a local attacker provides crafted input to a pre-installed app, causing it to write data beyond the allocated buffer. This can corrupt adjacent memory, potentially leading to control-flow hijacking and arbitrary code execution.

Root Cause: The flaw likely stems from insufficient bounds checking in a system service or library used by pre-installed apps. When processing attacker-controlled data, the application fails to validate the size or offset before writing to a buffer, allowing writes outside the intended memory region.

Attack Scenario: An attacker with local shell access or the ability to run a malicious app on the device can exploit this by sending specially crafted IPC messages or file data to a vulnerable pre-installed app. The out-of-bounds write corrupts critical data structures, such as function pointers or return addresses, enabling the attacker to execute arbitrary code with the privileges of the targeted app.

Vulnerable vs. Patched Code

Since no patch details are available, a generic comparison is provided based on common out-of-bounds write patterns.

Vulnerable Code (Conceptual):

void process_data(char *input, size_t len) {
    char buffer[256];
    // No bounds check on len
    memcpy(buffer, input, len);
}

Patched Code (Conceptual):

void process_data(char *input, size_t len) {
    char buffer[256];
    if (len > sizeof(buffer)) {
        // Handle error
        return;
    }
    memcpy(buffer, input, len);
}

The patched version adds a length check before the memory copy, preventing writes beyond the buffer size.

Exploitation & Lab Setup

Red Team (Exploitation):

1. Setup: Obtain a device running OpenHarmony v5.1.0. Gain local shell access via ADB or other means.
2. Craft Payload: Create a malicious input that triggers the out-of-bounds write. This may involve sending a large IPC message or a crafted file to a pre-installed app.
3. Trigger: Execute the payload to corrupt memory and hijack execution flow.
4. Escalate: Use the code execution to escalate privileges or exfiltrate data.

Blue Team (Defense):

1. Monitor: Deploy endpoint detection and response (EDR) agents on OpenHarmony devices to monitor for abnormal memory access patterns.
2. Harden: Restrict local access to devices. Use application sandboxing to limit the impact of code execution.
3. Audit: Review logs for crashes or unusual behavior in pre-installed apps.
4. Patch: Apply vendor patches as soon as they become available.

Indicators of Compromise (IOCs)

• File Hashes: (None available)
• Network Indicators: (None available)
• Behavioral Indicators:
  • Unexpected crashes in pre-installed applications.
  • Unusual memory access patterns detected by system monitors.
  • Presence of unknown processes or services running with elevated privileges.
  • Anomalous IPC traffic targeting pre-installed apps.

Detection Engineering

YARA Rule:

rule CVE_2025_52458_OOB_Write {
    meta:
        description = "Detects potential out-of-bounds write exploitation for CVE-2025-52458"
        author = "Valters IT"
        date = "2025-04-10"
        hash = "unknown"
    strings:
        $s1 = "memcpy" ascii wide nocase
        $s2 = "buffer" ascii wide nocase
    condition:
        all of them
}

Sigma Rule:

title: CVE-2025-52458 Out-of-Bounds Write Detection
id: 12345678-1234-1234-1234-123456789abc
status: experimental
description: Detects potential exploitation of CVE-2025-52458 via abnormal memory access
author: Valters IT
date: 2025-04-10
logsource:
    category: process_creation
    product: linux
detection:
    selection:
        Image|endswith: '/preinstalled_app'
        CommandLine|contains: '--large-input'
    condition: selection
falsepositives:
    - Legitimate large input processing
level: high

Suricata Rule:

alert ip any any -> any any (msg:"CVE-2025-52458 Potential OOB Write Exploit"; content:"|41 41 41 41|"; depth:100; sid:1000001; rev:1;)

Remediation & Mitigation

• Immediate: Restrict local access to OpenHarmony devices. Disable unnecessary pre-installed apps if possible.
• Short-term: Monitor vendor advisories for patches. Apply any available updates immediately.
• Long-term: Implement strict input validation and bounds checking in all system services and pre-installed applications. Conduct regular security audits of the codebase.

Valters IT
Securing Digital Frontiers