Analytics Alerts

Browse the Cortex analytics alert reference.

Severity
Detection module
Data source

1 alert match the current filters. technique: T1684 ✕

Download CSV Show ATT&CK heatmap
  • Suspicious DKIM Result Informational Email 4 variations

    The email contains a suspicious DKIM entry, showing either an unexpected verification result (none, fail, or policy) or a mismatched signing domain, which may indicate potential tampering or spoofing activity.

    Activation:
    14 Days
    Training:
    30 Days
    Test:
    N/A (single event)
    Deduplication:
    1 Day
    ATT&CK tactics: Stealth (TA0005)
    ATT&CK techniques: Social Engineering: Impersonation (T1684.001)
    Required data: Microsoft 365 Emails
    Detector tags: Spoofing
    Attacker's goals: Impersonate internal users or familiar individuals and trick them into clicking on malicious links or attachments.
    Investigative actions: Check the email address for any unusual spellings, missing letters, or unknown domains. Examine the sender's IP address and reputation, and check why DKIM didn't pass. Verify whether the sender's IP address has appeared in different log sources before, and if it is recognizable. If the message contains attachments or links, scrutinize them for any suspicious indications. Monitor further actions taken, such as file downloads or access to potentially malicious links.

    Variations

    Known domain DKIM deviation

    Informational overridden

    An email was sent from a commonly seen domain in the organization, that has historically passed DKIM checks, but returned a suspicious DKIM result of fail This deviation may indicate an attempt to spoof or impersonate a legitimate external sender. Such sudden DKIM outcome from a previously trusted external domain warrants further investigation. overridden

    Lack DKIM signature from typically signing domains

    Informational overridden

    An email was sent from a domain that has historically passed DKIM checks, but returned a suspicious DKIM result of none A none DKIM result implies on an unsigned email, which is atypical for domains with previous signed messages. This deviation may indicate an attempt to spoof or impersonate a legitimate external sender. Such sudden DKIM outcome from a previously trusted external domain warrants further investigation. overridden

    DKIM results lacking sender correlation

    Informational overridden

    The email's authentication results have no indication of proper signing from the email's sender This deviation may indicate an attempt to spoof or impersonate a legitimate external sender. overridden

    Known domain suspicious DKIM result

    Informational overridden

    An email was sent from a commonly seen domain that had no other suspicious DKIM outcomes for the past 30 days. This may indicate an attempt to spoof or impersonate a legitimate external sender. overridden