{"schemaVersion":3,"id":"CVE-2026-93394","aliases":["UBUNTU-CVE-2026-93394","DEBIAN-CVE-2026-93394"],"status":"published","duplicateOf":null,"title":null,"description":"A flaw in libmongoc's SCRAM authentication implementation caused the client to continue the authentication handshake and transmit the client proof even when a nonce mismatch was detected in the server's first message. An unauthorized party with a man-in-the-middle position could exploit this by injecting a crafted server-first-message containing a controlled salt and low iteration count, then capturing the resulting client proof to perform offline password cracking. 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