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Detection rules › Sublime MQL

DLP: Basic Authentication Header

Severity
medium
Type
dlp
Source
github.com/sublime-security/sublime-rules

Detects messages containing HTTP Basic Authentication headers.

Event coverage

Message attribute
body.current_thread
subject
type

Rule body MQL

type.outbound
and any([body.current_thread.text, subject.subject],
        // Basic auth format: "Basic " followed by base64
        regex.contains(., '\bBasic\s+[A-Za-z0-9+/]+=*\b')
)

Detection logic

Scope: outbound message.

Detects messages containing HTTP Basic Authentication headers.

  1. outbound message
  2. any of [body.current_thread.text, subject.subject] where:
    • . matches '\\bBasic\\s+[A-Za-z0-9+/]+=*\\b'

Inspects: body.current_thread.text, subject.subject, type.outbound. Sensors: regex.contains.

Indicators matched (1)

FieldMatchValue
regex.containsregex\bBasic\s+[A-Za-z0-9+/]+=*\b