How a cheap barcode scanner helped fix CrowdStrike’d Windows PCs in a flash

From theregister.com

Not long after Windows PCs and servers at the Australian limb of audit and tax advisory Grant Thornton started BSODing last Friday, senior systems engineer Rob Woltz remembered a small but important fact: When PCs boot, they consider barcode scanners no differently to keyboards.

That knowledge nugget became important as the firm tried to figure out how to respond to the mess CrowdStrike created, which at Grant Thornton Australia threw hundreds of PCs and no fewer than 100 servers into the doomloop that CrowdStrike’s shoddy testing software made possible.

All of Grant Thornton’s machines were encrypted with Microsoft’s BitLocker tool, which meant that recovery upon restart required CrowdStrike’s multi-step fix and entry of a 48-character BitLocker key.

The firm prioritized recovery for its servers, and tackled that task manually. But infrastructure manager Ben Watson and Woltz felt the sheer number of PCs at the firm meant an automated response would be required.

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