CVE-2025-24309: OpenAtom OpenHarmony RCE Vulnerability

CVE-2025-24309 Overview

CVE-2025-24309 is an out-of-bounds write vulnerability affecting OpenHarmony v5.0.2 and prior versions. The flaw allows a local attacker to achieve arbitrary code execution within pre-installed applications on affected devices. Exploitation is constrained to restricted scenarios, requiring local access and low-privileged execution context. The vulnerability is tracked under [CWE-787] and carries a CVSS v3.1 base score of 7.8. OpenAtom, the maintainer of OpenHarmony, published a security disclosure detailing the issue in March 2025. Because OpenHarmony is used in smart devices, IoT hardware, and embedded systems, this vulnerability affects both consumer and industrial deployments running the affected release stream.

Critical Impact
Local attackers can execute arbitrary code inside pre-installed applications on OpenHarmony v5.0.2 and earlier by triggering an out-of-bounds write.

Affected Products

OpenAtom OpenHarmony v5.0.2
OpenAtom OpenHarmony prior versions in the v5 branch
Devices and embedded systems shipping pre-installed apps based on the affected OpenHarmony builds

Discovery Timeline

2025-03-04 - CVE-2025-24309 published to NVD
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-24309

Vulnerability Analysis

The vulnerability is an out-of-bounds write ([CWE-787]) in OpenHarmony v5.0.2 and prior versions. An out-of-bounds write occurs when a program writes data past the end, or before the beginning, of an allocated buffer. In this case, the flaw resides in components accessible to pre-installed applications, allowing memory corruption within those app processes.

Successful exploitation gives the attacker arbitrary code execution in the context of the affected pre-installed application. Because the attack vector is local and requires low privileges, an attacker must already have code execution on the device, for example through a malicious or compromised app. The vendor advisory notes that exploitation is confined to restricted scenarios, which typically implies specific runtime conditions or pre-installed app entry points.

The impact covers confidentiality, integrity, and availability, since arbitrary code execution in the app process can access user data, modify application state, or crash the process. On IoT and mobile platforms, this class of memory corruption is frequently used as a stepping stone toward broader sandbox escapes or privilege escalation.

Root Cause

The root cause is missing or incorrect bounds validation on a write operation within an OpenHarmony component reachable by pre-installed apps. When the affected code path processes attacker-influenced input, it computes an index or length that exceeds the allocated buffer, corrupting adjacent memory. The OpenHarmony security bulletin references the specific module but does not disclose exploit-level detail. See the OpenHarmony Security Disclosure for the vendor's technical notes.

Attack Vector

Exploitation requires local access to a device running the vulnerable OpenHarmony build and the ability to invoke the affected interface from a pre-installed application context. An attacker with a foothold, such as a malicious sideloaded app or a compromised legitimate app, can craft input that triggers the out-of-bounds write and hijack execution within the target app process. Remote exploitation without prior device access is not indicated by the vendor advisory.

No public proof-of-concept exploit is available, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog.

Detection Methods for CVE-2025-24309

Indicators of Compromise

Unexpected crashes or SIGSEGV signals in pre-installed OpenHarmony application processes
Anomalous child processes spawned by pre-installed apps that normally do not fork external binaries
Modified files or unusual write activity in directories owned by pre-installed application UIDs

Detection Strategies

Inventory OpenHarmony devices in the environment and verify build versions against v5.0.2 and earlier
Monitor device logs (hilog) for repeated abnormal terminations of pre-installed applications, which can indicate exploitation attempts
Establish a behavioral baseline for pre-installed apps and alert on deviations such as new network connections or file writes outside their sandbox

Monitoring Recommendations

Forward OpenHarmony device telemetry and crash logs to a centralized log platform for correlation and retention
Track application package installations and updates on managed OpenHarmony devices to identify untrusted apps that could serve as local attack vectors
Review vendor security bulletins from OpenAtom on a recurring cadence to catch related advisories in the same component

How to Mitigate CVE-2025-24309

Immediate Actions Required

Upgrade all OpenHarmony devices from v5.0.2 and earlier to a fixed release as identified in the OpenHarmony Security Disclosure
Restrict installation of untrusted third-party applications on affected devices to reduce local attack surface
Audit pre-installed applications and remove any that are unused or unnecessary for device function

Patch Information

OpenAtom addressed CVE-2025-24309 in an OpenHarmony release following v5.0.2. Refer to the OpenHarmony Security Disclosure for the specific fixed version and patched commits. Device manufacturers integrating OpenHarmony should incorporate the upstream fix into their firmware builds and distribute updates to end users.

Workarounds

Where patching is not immediately possible, restrict physical and local access to affected devices
Enforce application allow-listing so only signed, trusted apps can execute on OpenHarmony devices
Disable or remove non-essential pre-installed applications that expose the vulnerable interface

bash

# Example: check OpenHarmony version on a device via hdc shell
hdc shell param get const.ohos.fullname
# Compare the returned build string against the fixed version listed in the vendor advisory