HarmonyosOperating system · Huawei

CVE-2026-34857

MEDIUM · 5.5 CVSS v3.1 Published 2026-04-13
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
57/100
Remediation priority · Elevated
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
UAF vulnerability in the communication module. Impact: Successful exploitation of this vulnerability may affect availability.

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 · moderate confidence

This is a Use-After-Free (UAF) vulnerability in a communication module. A UAF occurs when memory is accessed after it has been freed, which can lead to unpredictable behavior, crashes, or potential code execution. Given the CVSS 5.5 and availability impact, exploitation likely causes denial of service through crashes rather than data compromise.

MitigationRemediation involves correcting the memory management logic in the communication module to ensure all pointers are properly nullified or validated after freeing, and that free operations occur at appropriate points in the code execution flow. Apply any available vendor patches.

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
HarmonyosOperating system
Affected:= 5.1.0= 5.1.1= 6.0.0

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
None
Integrity
None
Availability
High

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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. Check HarmonyOS version installed
    Navigate to Settings > About Phone > Version on the device, or use the command 'getprop ro.build.version.harmonyos' via ADB or terminal to retrieve the installed HarmonyOS version number
    Affected if The displayed version matches 5.1.0, 5.1.1, or 6.0.0 exactly
  2. Identify active communication services
    Review running processes and services on the device that handle network communication, telephony, or messaging functions (visible in Settings > Apps > Running or via 'ps' command)
    Affected if Communication-related services or applications are actively running on the device
  3. Check for module-specific crashes
    Examine system crash logs using 'logcat -b crash' via ADB or review device bug reports for Use-After-Free errors or unexpected termination of communication-related processes
    Affected if Crash logs show memory corruption or UAF errors occurring in communication module components
  4. Verify communication module is enabled
    Inspect system settings or configuration for communication-related modules (such as network stack, telephony, or messaging services) to determine if the vulnerable module is actively enabled
    Affected if The communication module is present and enabled in the device configuration

The device is affected if it runs HarmonyOS version 5.1.0, 5.1.1, or 6.0.0 and has the vulnerable communication module enabled and operational, as the UAF flaw requires both the specific version and active use of the flawed module.

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.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Remediation involves correcting the memory management logic in the communication module to ensure all pointers are properly nullified or validated after freeing, and that free operations occur at appropriate points in the code execution flow. Apply any available vendor patches.

Fix this in Harmonyos Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA4.0 h
22.0 hours of engineering $3,860
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-34857 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

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-2026-34857 in production — separate from our analysis above.

No notes yet

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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