Attackers Abuse Legitimate Infrastructure to Distribute Phishing Emails

Preview text: Attackers Abuse Legitimate Infrastructure to Distribute Phishing Emails 96 KnowBe4…

Wednesday, Oct 28, 2026 at 9:03 AM EasternHubSpot

KnowBe4Attackers Abuse Legitimate Infrastructure to Distribute Phishing Emails

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Subject: Attackers Abuse Legitimate Infrastructure to Distribute Phishing Emails
Preview text: Attackers Abuse Legitimate Infrastructure to Distribute Phishing Emails 96 KnowBe4…
From: team@knowbe4.com
Brand: KnowBe4
ESP: HubSpot
Sent: Wed Oct 28, 2026, 9:03 AM ET
Sent to: blog.knowbe4.com
Size: 72 KB
Images: 11
Links: 11, 1 of them buttons
Subject length: 72 characters

Against KnowBe4's usual

Sent in its busiest hour, 9 AM, which holds 46% of its emails. The subject is 72 characters; its average is 61.

Email headers

What the brand's servers put on this email. Our receiving servers, the address we subscribed with and unsubscribe links are left out.

From: KnowBe4 Team <[email protected]>
Reply-To: [email protected]
Subject: Attackers Abuse Legitimate Infrastructure to Distribute Phishing Emails
Date: Wed, 28 Oct 2026 09:03:06 -0400
Message-ID domain: 241394m.knowbe4.com
Return-Path domain: 241394m.knowbe4.com
DKIM signature: d=241394m.knowbe4.com s=hs1; d=knowbe4.com s=hs2
List-Unsubscribe: Present, one-click
Feedback-ID sender: HubSpot

Other sending headers (names only): X-HS-Cid, X-Report-Abuse-To

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