External risk intelligence

Huawei EMUI and HarmonyOS Installd Module Parameter Verification Vulnerability.

CVE advisorySeverity: CRITICAL (CVSS 9.1)

CVE-2023-39401

The vulnerability affects the installd module within Huawei EMUI and HarmonyOS operating systems, which are mobile device platforms. This functionality is internal to the local device architecture and is not an internet-facing service, API, or network gateway. It is not designed to be reachable via the public internet.

Path Traversal

Huawei Emui

11.0.112.0.012.0.113.0.02.0.02.0.12.1.03.0.03.1.0

Halo Surface Signal: 1 out of 5 — much less likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

This advisory concerns a critical vulnerability in Huawei's EMUI and HarmonyOS. The flaw allows unauthorized reading and writing of sandbox files, which could potentially impact the integrity and confidentiality of data within those environments. The main concern is confirming relevance and exposure to these specific operating systems.

Flaw allows unauthorized file access.
Internal mobile OS issue, check relevance.
Confirm if your systems are affected.

Attack Path

How an attacker could exploit the issue

Attackers can reach the vulnerable installd module over the network, which is part of Huawei EMUI and HarmonyOS. This module is responsible for verifying parameters during installation processes. If an attacker can interact with this module, they may be able to bypass security checks, allowing unauthorized reading and writing of sandbox files.

Accessible via the network.
Exploits parameter verification.
Enables unauthorized file access.

Live Threat

Current exploitation, exposure, and threat context

A parameter verification flaw in the installd module could allow unauthorized reading and writing of sandbox files when supported by the advisory. This could affect system files and sensitive information stored within sandboxed environments on affected devices.

System files and sandbox data at risk.
Unauthorized read/write access to sandbox.
Potential for data corruption or leakage.

Operational Fix

Recommended remediation, mitigation, and detection steps

This vulnerability in the installd module affects Huawei devices running EMUI and HarmonyOS. Identifying the presence of the affected operating systems, confirming their reachability and criticality, and then locating the responsible owner are the first practical steps. Remediation planning should follow based on a risk assessment.

Mobile device owners and platform teams.
Verify device reachability and business criticality.
Plan remediation based on identified risk.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

Halo Threat Intelligence helps prioritize remediation with Halo Surface Signal and H/A/L/O context. Start exposure validation with a free external attack surface trial.

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Frequently asked questions

What is the installd module in Huawei EMUI and HarmonyOS?

The installd module is a core system component within Huawei's EMUI and HarmonyOS mobile operating systems. Its primary function is to manage and verify parameters during the installation or updates of applications on the device. By ensuring that software installations follow established rules, it helps maintain the integrity of the device's file structure and the isolation of individual app environments.

What does CVE-2023-39401 mean by parameter verification vulnerability?

This vulnerability, classified under CWE-22 (Path Traversal) and CWE-285 (Improper Authorization), means the system fails to properly validate inputs provided to the installd module. Because the module does not check these parameters correctly, it can be tricked into performing actions outside its intended scope, allowing unauthorized reading or writing of files within the device's secure application sandbox.

How is this vulnerability triggered in the installd module?

The flaw is triggered when an attacker interacts with the installd module over a network connection to provide malicious parameters. Importantly, standard local usage of applications or normal device operation does not trigger this issue. The vulnerability specifically requires successful manipulation of the verification logic used during installation-related tasks to bypass authorization checks.

Is my device at risk based on Halo Surface Signal?

Halo Surface Signal indicates that this vulnerability is very unlikely to be exploited from the internet. Because the installd module is an internal component of mobile device platforms and not an internet-facing service or network gateway, it is not designed to be reachable by external network traffic, significantly limiting the potential attack surface for most users.

What should I do if I manage devices running these versions?

Begin by identifying which of your managed devices are running the affected versions of EMUI or HarmonyOS. Once identified, prioritize devices based on their business criticality and how they are used within your environment. Consult Huawei's official security bulletins to locate authorized updates and coordinate a plan to apply these patches to the affected hardware.

References

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.