How Attackers Bypass Synced Passkeys
Oct 15, 2025
Data Protection / Browser Security
TLDR Even if you take nothing else away from this piece, if your organization is evaluating passkey deployments, it is insecure to deploy synced passkeys. Synced passkeys inherit the risk of the cloud accounts and recovery processes that protect them, which creates material enterprise exposure. Adversary-in-the-middle (AiTM) kits can force authentication fallbacks that circumvent strong authentication all together Malicious or compromised browser extensions can hijack WebAuthn requests, manipulate passkey registration or sign-in, and drive autofill to leak credentials and one-time codes. Device-bound passkeys in hardware security keys offer higher assurance and better administrative control than synced passkeys, and should be mandatory for enterprise access use cases Synced Passkey Risks Synced passkey vulnerabilities Passkeys are credentials stored in an authenticator. Some are device-bound, others are synced across devices through consumer cloud services like iCloud and Go...