EmuiOperating system · Huawei

CVE-2021-36995

HIGH · 7.5 CVSS v3.1 Published 2021-10-28
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
84/100
Remediation priority · High
Remotely reachable No privileges 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
There is an Unauthorized file access vulnerability in Huawei Smartphone.Successful exploitation of this vulnerability by modifying soft links may tamper with the files restored from backups.

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 vulnerability in Huawei smartphones allows unauthorized file access through soft link manipulation during the backup restoration process. An attacker could modify symbolic links to tamper with files being restored from backups, potentially overwriting or corrupting system files.

MitigationApply vendor-provided security patches from Huawei. Until a patch is available, avoid restoring backups from untrusted sources and monitor for unusual file system activity.

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
EmuiOperating system
Affected:= 10.1.1= 11.0.0
Magic UiOperating system
Affected:= 3.1.1= 4.0.0

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
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
None

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

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 your EMUI or Magic UI version
    Go to Settings > About Phone > Version on your Huawei device. Alternatively, dial *#*#2846579#*#* to access the engineering menu and view the SW version information.
    Affected if The installed version is exactly 10.1.1 or 11.0.0 for EMUI, or exactly 3.1.1 or 4.0.0 for Magic UI.
  2. Identify if backup restoration was performed
    Review your device logs or check recently restored backup files in your device storage or cloud backup history.
    Affected if A backup from an untrusted or third-party source was restored to the device.
  3. Inspect for modified system files
    Use a file manager with root access or ADB shell to compare critical system files (such as /system, /vendor partitions) against known good hashes or baseline snapshots.
    Affected if System files show unexpected modifications or ownership changes that were not initiated by official system updates.
  4. Look for suspicious symbolic links
    Search the backup restoration directories and common staging areas (such as /data/local/tmp or the backup cache folder) for symbolic links pointing to sensitive system paths.
    Affected if Symbolic links exist that redirect restore paths to system directories like /system or /data.

You are affected if your device runs EMUI 10.1.1, 11.0.0, Magic UI 3.1.1, or 4.0.0 and you have restored a backup from an untrusted source, with evidence of unexpected system file changes or symlink manipulation present.

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

Apply vendor-provided security patches from Huawei. Until a patch is available, avoid restoring backups from untrusted sources and monitor for unusual file system activity.

Fix this in Emui Scoped from the published advisory
  • Consultation4.0 h
  • Implementation2.0 h
  • Testing8.0 h
  • Review / QA4.0 h
18.0 hours of engineering $3,080
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2021-36995 — 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-2021-36995 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