Post by jabom on Dec 28, 2023 6:47:30 GMT 1
Since the email has its DKIM signature intact from the high-reputation domain, email servers are more likely to trust it, thinking it’s a legitimate message – thereby bypassing authentication filters. Steps to Prevent DKIM Replay Attacks DKIM replay attack prevention strategies for email senders: . Oversigning Headers To ensure that key headers like Date, Subject, From, To, and CC or modified after signing, consider over-signing them. This safeguard prevents malicious actors from tampering.
With these critical message components. . Setting Job Function Email List Short Expiration Times (x=) Implement as brief an expiration time (x=) as practically possible. This reduces the window of opportunity for replay attacks. Newly created domains must have an even shorter expiration time than older ones as they are more vulnerable to attacks. . Employing Timestamps (t=) and Nonces To further prevent replay attacks, include timestamps and nonces (random numbers) in the email headers or body. This makes it difficult for attackers to resend the same email at a later time because the values would have changed.
Rotating DKIM keys Periodically Rotate DKIM keys regularly and update your DNS records accordingly. This minimizes the exposure of long-lived keys that could be compromised and used in replay attacks. DKIM replay attack prevention strategies for email receivers: . Implementing Rate Limiting Receivers may implement rate limiting on incoming email messages to prevent attackers from flooding your system with replayed emails. To do so you can set limits on the number of emails accepted from a specific sender.
With these critical message components. . Setting Job Function Email List Short Expiration Times (x=) Implement as brief an expiration time (x=) as practically possible. This reduces the window of opportunity for replay attacks. Newly created domains must have an even shorter expiration time than older ones as they are more vulnerable to attacks. . Employing Timestamps (t=) and Nonces To further prevent replay attacks, include timestamps and nonces (random numbers) in the email headers or body. This makes it difficult for attackers to resend the same email at a later time because the values would have changed.
Rotating DKIM keys Periodically Rotate DKIM keys regularly and update your DNS records accordingly. This minimizes the exposure of long-lived keys that could be compromised and used in replay attacks. DKIM replay attack prevention strategies for email receivers: . Implementing Rate Limiting Receivers may implement rate limiting on incoming email messages to prevent attackers from flooding your system with replayed emails. To do so you can set limits on the number of emails accepted from a specific sender.