AgreeToSteal
AgreeToSteal is malware identified as a malicious Microsoft Outlook add-in. The provided content describes it as the first malicious Outlook add-in and states that it led to 4,000 stolen credentials. It is referenced in Security Affairs coverage dated February 15, 2026, in the article titled “AgreeToSteal: The First Malicious Outlook Add-In Leads to 4,000 Stolen Credentials.” No additional high-confidence details about its infection vector, technical behavior beyond being an Outlook add-in, associated threat actors, targeted industries, platforms beyond Outlook, or specific indicators of compromise are provided in the source content.
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Techniques & procedures
2 distinct techniques documented for this family, organized by ATT&CK tactic.
Recent activity
2 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
Malicious Microsoft Outlook add-in used to steal user credentials.
AgreeToSteal: The First Malicious Outlook Add-In Leads to 4,000 Stolen Credentials
The version that knows your environment.
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Named campaigns wielding this family, with evidence pinned to each claim.
CVEs this family uses for access and lateral movement.
YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.
Every documented technique, ranked by evidence weight.
Reddit, Mastodon, and CTI community discussion around this family.