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“Police CyberAlarm uses the same encryption key for both AES-CBC encryption and for HMAC-SHA256.”

Scott Arciszewskiscottarc.blog ↗

UK police hand this software to businesses to monitor their networks. It reuses one key for encryption and authentication, and stripping a length prefix skips the HMAC check entirely. That leaves unauthenticated AES-CBC open to a padding oracle. The cops selling cyber safety shipped textbook mistakes from 2010.