Patch CVE-2026-66066 in Active Storage variant processing - #102
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Upgrade rails/activestorage 8.1.3 -> 8.1.3.1 (8-1-stable), which disables libvips' unsafe "unfuzzed" format loaders/savers that allowed arbitrary file read and RCE via crafted image uploads. Add a defense-in-depth initializer calling Vips.block_untrusted(true) so untrusted loaders stay blocked even if variant processing is introduced later. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Addresses CVE-2026-66066, a critical Active Storage flaw where libvips' unsafe "unfuzzed" format loaders/savers allowed arbitrary file read and RCE via crafted image uploads (we accept an org
logoupload). Upgradesrails/activestoragefrom 8.1.3 to 8.1.3.1 (via the8-1-stablebranch), which ships the fix. Adds a defense-in-depth initializer callingVips.block_untrusted(true)so untrusted loaders stay blocked even if variant processing is introduced later. Full test suite passes (263 runs, 0 failures), including the logo-upload flow.🤖 Generated with Claude Code