CVE-2026-44359

Description

Meshtastic is an open source mesh networking solution. Prior to version 2.7.21.1370b23, the Meshtastic GitHub repository's main_matrix.yml workflow is triggered by pull_request_target and multiple jobs check out the attacker's fork code and execute it with access to repository secrets and elevated GITHUB_TOKEN permissions. No approval gate exists. Pull requests from external users with author_association: "NONE" triggered the CI workflow automatically. The workflow directly executes attacker-controlled files from the fork checkout. This issue could have resulted in supply chain compromise, self-hosted runner compromise, and/or repository takeover for the repo. This issue is separate from GHSA-6mwm-v2vv-pp96, which addressed a command injection via github.head_ref in the setup job of the same workflow. That fix correctly moved to environment variables. However, the more critical fork checkout vulnerability across the check, build, and build-debian-src jobs was not addressed. Version 2.7.21.1370b23 contains a patch for thie issue.

References

• https://drive.google.com/file/d/1GdHT2s5hMYCiHt4zrWt1q58mvL7WQC0M/view?usp=sharing
• https://github.com/meshtastic/firmware/commit/5716aeba3bc1e1d34fba9567ff88917ede4a78a5
• https://github.com/meshtastic/firmware/security/advisories/GHSA-6mwm-v2vv-pp96
• https://github.com/meshtastic/firmware/security/advisories/GHSA-mjx5-98jq-q736