L9Operating system · Mediatek

CVE-2021-40148

HIGH · 7.5 CVSS v3.1 Published 2022-01-04
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
In Modem EMM, there is a possible information disclosure due to a missing data encryption. This could lead to remote information disclosure with no additional execution privileges needed. User interaction is not needed for exploitation. Patch ID: MOLY00716585; Issue ID: ALPS05886933.

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 exists in the modem's EPS Mobility Management (EMM) layer where data that should be encrypted is being transmitted in plaintext, allowing remote attackers to intercept sensitive mobility management information without authentication or user interaction.

MitigationApply the vendor firmware patch (MOLY00716585) to affected cellular modem implementations to enforce proper data encryption in the EMM layer.

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
L9Operating system
Affected:all versions
Lr11Operating system
Affected:all versions
Lr12Operating system
Affected:all versions
Lr12aOperating system
Affected:all versions
Lr13Operating system
Affected:all versions
Nr15Operating system
Affected:all versions

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
High
Integrity
None
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/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. Identify Mediatek modem model in use
    Query the cellular modem for its model using AT commands (e.g., AT+CGMM or ATI) or inspect hardware specifications and device inventory records
    Affected if The modem model is any of: L9, Lr11, Lr12, Lr12a, Lr13, or Nr15
  2. Retrieve modem firmware version
    Query the modem firmware version using AT commands such as AT+CGMR or AT+GMR, or check the firmware manifest on the device
    Affected if A version is returned and the modem is one of the affected models listed above
  3. Verify patch inclusion
    Compare the installed firmware version against the patched version MOLY00716585, or check vendor release notes to confirm the patch is incorporated in the current firmware build
    Affected if The firmware version is older than the patched build containing MOLY00716585, or the patch status cannot be confirmed
  4. Confirm EMM plaintext transmission is active
    Capture and inspect cellular network traffic (using a protocol analyzer or network monitoring tool) for unencrypted EMM messages between the modem and base station
    Affected if EPS Mobility Management messages are observed in plaintext rather than encrypted

You are affected if your environment contains any Mediatek modem model L9, Lr11, Lr12, Lr12a, Lr13, or Nr15 running firmware without the MOLY00716585 patch.

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 the vendor firmware patch (MOLY00716585) to affected cellular modem implementations to enforce proper data encryption in the EMM layer.

Fix this in L9 Scoped from the published advisory
  • Consultation4.0 h
  • Implementation6.0 h
  • Testing4.0 h
  • Review / QA2.0 h
16.0 hours of engineering $2,840
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Scan for this in your stack

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dbcve dependency scanner

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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-2021-40148 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