Meshtastic FirmwareOperating system · Meshtastic

CVE-2025-53637

HIGH · 8.0 CVSS v3.1 Published 2025-07-10
Fix available
A fix is available. Upgrade to 2.6.6 or later.
See remediation →
84/100
Remediation priority · High
Remotely reachable

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
Meshtastic is an open source mesh networking solution. The main_matrix.yml GitHub Action is triggered by the pull_request_target event, which has extensive permissions, and can be initiated by an attacker who forked the repository and created a pull request. In the shell code execution part, user-controlled input is interpolated unsafely into the code. If this were to be exploited, attackers could inject unauthorized code into the repository. This vulnerability is fixed in 2.6.6.

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

The main_matrix.yml GitHub Action uses pull_request_target trigger which runs with elevated permissions on the base repository. An attacker can fork the repo, create a malicious pull request, and have their code execute in the context of the base repository's elevated permissions due to unsafe interpolation of user-controlled input into shell command execution.

MitigationUpgrade to Meshtastic version 2.6.6 or later, which contains the fix. Additionally, review and sanitize all user inputs in GitHub Actions workflows and consider using pull_request instead of pull_request_target for untrusted contributions.

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
Meshtastic FirmwareOperating system
Affected:< 2.6.6

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
Low
User interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/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. Check installed Meshtastic firmware version
    Connect to your Meshtastic device and run 'meshtastic --info' or check the device UI to view the firmware version installed
    Affected if The displayed firmware version is lower than 2.6.6 (e.g., 2.6.5, 2.5.x, etc.)
  2. Identify the build system used
    Examine your local or forked Meshtastic repository for .github/workflows/main_matrix.yml or similar workflow files
    Affected if The repository contains GitHub Actions workflows using pull_request_target trigger with shell command execution
  3. Inspect workflow for unsafe variable interpolation
    Open the workflow YAML file and search for instances where user-controlled variables (such as github.event.pull_request.title, body, or head.ref) are directly interpolated into run: commands without proper sanitization
    Affected if The workflow uses ${{ github.event.pull_request.* }} or ${{ steps.*.outputs.* }} directly in shell commands without escaping or input validation

You are affected if your Meshtastic firmware version is below 2.6.6 AND your build process uses the vulnerable GitHub Actions workflow with pull_request_target and unsafe input interpolation.

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 2.6.6 or later
Fixed in 2.6.6
Interim mitigation

Upgrade to Meshtastic version 2.6.6 or later, which contains the fix. Additionally, review and sanitize all user inputs in GitHub Actions workflows and consider using pull_request instead of pull_request_target for untrusted contributions.

Recommended fix High confidence

Meshtastic Firmware 2.6.6

  1. Upgrade Meshtastic Firmware to version 2.6.6 or later to obtain the fixed GitHub Action workflow

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

Fix this in Meshtastic Firmware Scoped from the published advisory
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing1.0 h
  • Review / QA1.0 h
6.0 hours of engineering $1,090
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,744.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2025-53637 — 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-2025-53637 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

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