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OpenharmonyApplication

CVE-2022-42464

HIGH · 7.8 CVSS v3.1 Published 2022-10-14
Fix available
A fix is available. Upgrade to after 3.1.2 or later.
See remediation →
80/100
Remediation priority · High
Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
OpenHarmony-v3.1.2 and prior versions, 3.0.6 and prior versions have a Kernel memory pool override vulnerability in /dev/mmz_userdev device driver. The impact depends on the privileges of the attacker. The unprivileged process run on the device could disclose sensitive information including kernel pointer, which could be used in further attacks. The processes with system user UID run on the device would be able to mmap memory pools used by kernel and override them which could be used to gain kernel code execution on the device, gain root privileges, or cause device reboot.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

OpenHarmony versions 3.1.2 and prior contain a kernel memory pool override vulnerability in the /dev/mmz_userdev device driver. Unprivileged processes can read sensitive kernel pointers from the memory pool, while processes with system UID can map and overwrite kernel memory pools to achieve code execution, root escalation, or device denial of service.

MitigationRestrict access to /dev/mmz_userdev by implementing proper permission checks in the driver and ensuring only authorized processes can mmap kernel memory pools. For unprivileged processes, disable or restrict access to this device; for system UID processes, validate all memory pool operations.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
OpenharmonyApplication
Affected:>= 3.0, <= 3.0.6>= 3.1, <= 3.1.2

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify OpenHarmony version
    Run 'getprop ro.build.version.sdk' or check '/proc/version' or '/etc/version' to determine the installed OpenHarmony version
    Affected if version is 3.0.x where x <= 6, or 3.1.x where x <= 2
  2. Verify /dev/mmz_userdev device exists
    Check if the device file /dev/mmz_userdev exists using 'ls -la /dev/mmz_userdev'
    Affected if the device file exists on the system
  3. Check device file permissions
    Run 'ls -la /dev/mmz_userdev' to inspect owner, group, and world read/write/execute permissions
    Affected if device has world-read/write (CRW-rw-rw-) or group-read/write permissions allowing broad access
  4. Verify process access to device
    Use 'ls -la /dev/mmz_userdev' and check if unprivileged users or processes without system UID can access the device; verify using 'cat /proc/[pid]/status | grep Uid' for processes using the device
    Affected if unprivileged processes or non-system UID processes have access to mmap or read from the device

The system is affected if it runs OpenHarmony 3.0 through 3.0.6 or 3.1 through 3.1.2 AND the /dev/mmz_userdev device exists with permissions allowing broad or unprivileged access.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to a release after 3.1.2
Interim mitigation

Restrict access to /dev/mmz_userdev by implementing proper permission checks in the driver and ensuring only authorized processes can mmap kernel memory pools. For unprivileged processes, disable or restrict access to this device; for system UID processes, validate all memory pool operations.

Recommended fix Moderate confidence

OpenHarmony 3.1.3 or later (3.1 branch); OpenHarmony 3.0.7 or later (3.0 branch)

  1. Identify the current OpenHarmony version running on the device using the system build information
  2. Upgrade OpenHarmony to version 3.1.3 or later for the 3.1 branch, or 3.0.7 or later for the 3.0 branch
  3. Verify the fix by confirming that /dev/mmz_userdev device no longer allows unprivileged or system UID processes to mmap and override kernel memory pools
  4. If immediate upgrade is not possible, review device driver permissions and restrict access to /dev/mmz_userdev to only essential privileged operations

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Openharmony Scoped from the published advisory
  • Consultation6.0 h
  • Implementation12.0 h
  • Testing10.0 h
  • Review / QA4.0 h
32.0 hours of engineering $5,580
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2022-42464 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data