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Firefox blocks my GitHub Actions firmware ZIP as malware despite a clean antivirus scan

Eugene Kishinevsky

Hello,

I'm building custom firmware for a Makerdiary nRF52840 USB dongle using GitHub Actions.

When I tried downloading the generated ZIP file, Firefox blocked it with the warning: "This file contains a virus or malware."

I removed the blocked download rather than overriding Firefox's protection.

The ZIP contains custom `.uf2` firmware for an embedded USB device. The GitHub Actions build passed its validation checks, and an independent ClamAV scan of the original firmware reported 0 infected files. I subsequently built and scanned an updated version, which also passed.

Original blocked build: https://github.com/flips96-art/hid-remapper/actions/runs/39094413639

Latest build: https://github.com/flips96-art/hid-remapper/actions/runs/39096517313

Latest antivirus scan: https://github.com/flips96-art/hid-remapper/actions/runs/39096868117

I understand that a clean ClamAV scan does not guarantee the file is safe.

Could someone help me determine why Firefox classified this download as malware and explain how to submit it for a possible false-positive review without disabling Firefox's security protections?

Thank you!

Hello, I'm building custom firmware for a Makerdiary nRF52840 USB dongle using GitHub Actions. When I tried downloading the generated ZIP file, Firefox blocked it with the warning: "This file contains a virus or malware." I removed the blocked download rather than overriding Firefox's protection. The ZIP contains custom `.uf2` firmware for an embedded USB device. The GitHub Actions build passed its validation checks, and an independent ClamAV scan of the original firmware reported 0 infected files. I subsequently built and scanned an updated version, which also passed. Original blocked build: https://github.com/flips96-art/hid-remapper/actions/runs/39094413639 Latest build: https://github.com/flips96-art/hid-remapper/actions/runs/39096517313 Latest antivirus scan: https://github.com/flips96-art/hid-remapper/actions/runs/39096868117 I understand that a clean ClamAV scan does not guarantee the file is safe. Could someone help me determine why Firefox classified this download as malware and explain how to submit it for a possible false-positive review without disabling Firefox's security protections? Thank you!

All Replies (1)

Hi, Firefox uses Google Malware Protection, please read How does built-in Phishing and Malware Protection work?

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