Lr12aOperating system · Mediatek

CVE-2025-20726

HIGH · 7.5 CVSS v3.1 Published 2025-11-04
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
81/100
Remediation priority · High
Remotely reachable 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, there is a possible out of bounds write due to an incorrect bounds check. This could lead to remote escalation of privilege, if a UE has connected to a rogue base station controlled by the attacker, with no additional execution privileges needed. User interaction is not needed for exploitation. Patch ID: MOLY01672598; Issue ID: MSV-4622.

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

An out-of-bounds write vulnerability exists in the modem component due to an incorrect bounds check. An attacker controlling a rogue base station can exploit this to achieve remote privilege escalation on a connected User Equipment (UE) device without any user interaction or pre-existing privileges.

MitigationApply vendor patch MOLY01672598 to the modem firmware via OTA update from the device manufacturer. Until patched, users should avoid connecting to untrusted or unknown base stations.

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
Lr12aOperating system
Affected:all versions
Nr15Operating system
Affected:all versions
Nr16Operating system
Affected:all versions
Nr17Operating system
Affected:all versions
Nr17rOperating 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
High
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:H/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 your device modem chipset
    Check device specifications, boot logs (dmesg), or AT command interface (AT+CGMM or AT+CGMI) to determine if the device uses a Mediatek modem chip. Look for chip identifiers such as MT67xx, Lr12a, Nr15, Nr16, Nr17, or Nr17r in system information.
    Affected if The device contains any of the following Mediatek modem chips: Lr12a, Nr15, Nr16, Nr17, or Nr17r. All versions of these chips are affected.
  2. Verify modem firmware version
    Access the modem diagnostic interface (typically via AT commands on serial/USB serial port, or through manufacturer service mode) and query the firmware version using AT+CGMR or AT+CGMR=? commands, or check system logs for modem firmware strings.
    Affected if The modem firmware version is any version prior to the vendor patch MOLY01672598, though note all versions of the listed chips are currently affected since no patch has been distributed.
  3. Check for mobile network connectivity capability
    Determine if the device has cellular/mobile network functionality enabled. Check device settings for cellular/mobile data, inspect if the device has a SIM slot, and verify if rfkill or similar tools show a cellular radio (run 'rfkill list all' or check Network Manager for cellular interfaces).
    Affected if The device has an active cellular radio and can connect to mobile networks, making it potentially reachable by a rogue base station.
  4. Assess exposure to unknown base stations
    Review device behavior and logs for connections to unexpected or anonymous base stations. Check if the device automatically connects to any available network without user verification. Monitor for unusual cell tower connections in device logs or through field test mode (AT+CREG?).
    Affected if The device automatically connects to untrusted or unknown base stations without user control or verification, creating the attack surface for this vulnerability.

A user is affected if their device contains a Mediatek Lr12a, Nr15, Nr16, Nr17, or Nr17r modem chip with cellular connectivity enabled, as the vulnerability can be triggered remotely by a rogue base station without any user interaction.

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 patch MOLY01672598 to the modem firmware via OTA update from the device manufacturer. Until patched, users should avoid connecting to untrusted or unknown base stations.

Fix this in Lr12a Scoped from the published advisory
  • Consultation3.0 h
  • Implementation6.0 h
  • Testing5.0 h
  • Review / QA2.0 h
16.0 hours of engineering $2,790
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Scan for this in your stack

Free · runs locally
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-2025-20726 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
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