Abnormal Security incident
Emails Incorrectly Remediated – Inbound Email Security and AI Security Mailbox
Abnormal Security experienced a notice incident on May 18, 2026 affecting Inbound Email Security (IES) and AI Security Mailbox (AISM), lasting —. The incident has been resolved; the full update timeline is below.
Affected components
Inbound Email Security (IES)AI Security Mailbox (AISM)
Update timeline
- resolved May 18, 2026, 11:24 PM UTC
Starting at 22:00 UTC on May 18, 2026, Abnormal identified an increase in legitimate emails being incorrectly flagged as malicious and remediated, impacting Inbound Email Security and AI Security Mailbox. The engineering team identified and disabled the rule responsible for falsely flagging these emails at 22:52 UTC. Messages affected during the impact window will be reprocessed.