detection.wiki

Detection rules › Sublime MQL

DLP: Private Key

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

Detects messages containing private keys (RSA, SSH, PGP).

Event coverage

Message attribute
body.current_thread
subject
type

Rule body MQL

type.outbound
and any([body.current_thread.text, subject.subject],
        regex.contains(., '-----BEGIN\s+(?:RSA\s+)?PRIVATE\s+KEY-----')
        or regex.contains(., '-----BEGIN\s+OPENSSH\s+PRIVATE\s+KEY-----')
        or regex.contains(., '-----BEGIN\s+PGP\s+PRIVATE\s+KEY\s+BLOCK-----')
        or regex.contains(., '-----BEGIN\s+EC\s+PRIVATE\s+KEY-----')
)

Detection logic

Scope: outbound message.

Detects messages containing private keys (RSA, SSH, PGP).

  1. outbound message
  2. any of [body.current_thread.text, subject.subject] where any holds:
    • . matches '-----BEGIN\\s+(?:RSA\\s+)?PRIVATE\\s+KEY-----'
    • . matches '-----BEGIN\\s+OPENSSH\\s+PRIVATE\\s+KEY-----'
    • . matches '-----BEGIN\\s+PGP\\s+PRIVATE\\s+KEY\\s+BLOCK-----'
    • . matches '-----BEGIN\\s+EC\\s+PRIVATE\\s+KEY-----'

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

Indicators matched (4)

FieldMatchValue
regex.containsregex-----BEGIN\s+(?:RSA\s+)?PRIVATE\s+KEY-----
regex.containsregex-----BEGIN\s+OPENSSH\s+PRIVATE\s+KEY-----
regex.containsregex-----BEGIN\s+PGP\s+PRIVATE\s+KEY\s+BLOCK-----
regex.containsregex-----BEGIN\s+EC\s+PRIVATE\s+KEY-----