CVE-2025-26474

Executive Summary

CVE-2025-26474 is a low-severity vulnerability in OpenHarmony v5.0.3 and prior versions that allows a local attacker to cause improper input validation. The vulnerability has a CVSS score of 3.3 and an EPSS score of 0.0%, indicating a very low probability of exploitation in the wild. The attack requires local access and low privileges, and can only be exploited in restricted scenarios. No public proof-of-concept or exploit code is available at this time.

Supply Chain & Package Security

This vulnerability affects the OpenHarmony operating system, which is an open-source distributed operating system. The vulnerability is not related to any specific package manager (NPM, PyPI, Go, Ruby) but rather to the core operating system components. Organizations using OpenHarmony in their supply chain should monitor for official patches and updates.

CVSS Breakdown & Threat Level

• CVSS Score: 3.3 (Low)
• Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
• Attack Vector: Local (AV:L)
• Attack Complexity: Low (AC:L)
• Privileges Required: Low (PR:L)
• User Interaction: None (UI:N)
• Scope: Unchanged (S:U)
• Confidentiality Impact: None (C:N)
• Integrity Impact: None (I:N)
• Availability Impact: Low (A:L)

The low CVSS score and EPSS probability of 0.0% indicate that this vulnerability is not currently a priority for threat actors. However, it should still be addressed as part of a comprehensive security posture.

Deep Dive & Mechanics

The vulnerability lies in improper input validation within OpenHarmony. A local attacker with low privileges can exploit this flaw to cause an availability impact. The exact mechanism is not publicly documented, but based on the CWE-20 classification, it likely involves insufficient sanitization of user-supplied input, leading to a denial-of-service condition.

The restricted scenarios for exploitation suggest that specific conditions must be met, such as a particular system state or configuration. This limits the attack surface significantly.

Vulnerable vs. Patched Code

No specific code snippets are available for this vulnerability. The vulnerable versions are OpenHarmony v5.0.3 and prior. The patched version is unknown, as no official patch has been released at this time.

Exploitation & Lab Setup

Red Team

No public exploit code is available for CVE-2025-26474. To test this vulnerability in a lab environment, a red team would need to:

1. Set up an OpenHarmony v5.0.3 system.
2. Gain local access with low privileges.
3. Attempt to trigger the improper input validation by sending malformed input to the vulnerable component.
4. Monitor for denial-of-service conditions.

Since no exploit code is available, this would require reverse engineering the vulnerable component.

Blue Team

Blue teams should:

1. Monitor for unusual local activity on OpenHarmony systems.
2. Implement strict input validation on all system interfaces.
3. Restrict local access to trusted users only.
4. Monitor system logs for signs of exploitation attempts.

Indicators of Compromise (IOCs)

No specific IOCs are available for this vulnerability. General indicators may include:

• Unexpected system crashes or reboots
• System logs showing failed input validation attempts
• Unusual process terminations

Detection Engineering

YARA Rule

rule CVE_2025_26474_OpenHarmony_InputValidation {
    meta:
        description = "Detects potential exploitation of CVE-2025-26474 in OpenHarmony"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2025-26474"
    strings:
        $s1 = "OpenHarmony" nocase
        $s2 = "5.0.3" nocase
        $s3 = "input validation" nocase
    condition:
        all of them
}

Sigma Rule

title: CVE-2025-26474 - OpenHarmony Improper Input Validation
id: 12345678-1234-1234-1234-123456789012
status: experimental
description: Detects potential exploitation of CVE-2025-26474 in OpenHarmony
author: Valters IT
date: 2025-04-10
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2025-26474
logsource:
    product: linux
    service: syslog
detection:
    selection:
        - "OpenHarmony"
        - "input validation"
        - "5.0.3"
    condition: selection
falsepositives:
    - Legitimate system operations
level: low

Suricata Rule

alert ip any any -> any any (msg:"CVE-2025-26474 - OpenHarmony Improper Input Validation"; content:"OpenHarmony"; content:"5.0.3"; content:"input validation"; classtype:attempted-dos; sid:1000001; rev:1;)

Remediation & Mitigation

1. Patch: Monitor OpenHarmony official channels for a patch. Apply it as soon as it becomes available.
2. Mitigation: Restrict local access to trusted users only. Implement strict input validation on all system interfaces.
3. Workaround: If possible, disable the vulnerable component or service until a patch is available.
4. Monitoring: Implement the detection rules provided above to monitor for exploitation attempts.

Valters IT
Securing Digital Frontiers