kevmap

TechniquesT1573.002 › AN1497

AN1497 Analytic 1497

Linux · attack.mitre.org · ATT&CK Enterprise v19.2

<p>Processes (e.g., bash, python, custom binaries) dynamically linking libcrypto/libssl for RSA key exchange, then creating external connections with abnormal certificate validation or handshake anomalies. Defender observes syscall traces and outbound asymmetric key exchanges from non-SSL-native processes.</p>
Detects
T1573.002 Asymmetric Cryptography
Part of
DET0543 Detection Strategy for Encrypted Channel via Asymmetric Cryptography across OS Platforms

Log sources and channels

Exactly as MITRE states them in x_mitre_log_source_references. Where a channel is vague, it is vague in the source; kevmap does not tidy it.

Log sourceChannelData component
auditd:SYSCALLexecve or socket/connect system calls for processes using RSA handshakeDC0032 Process Creation
linux:syslogNon-standard processes negotiating SSL/TLS key exchangesDC0038 Application Log Content
linux:osqueryProcesses linked with libssl/libcrypto performing network activityDC0016 Module Load

Mutable elements

Parameters MITRE marks as environment-specific. These are the knobs you are expected to tune; they are why an analytic is not a rule.

FieldDescription
ExpectedCryptoLibsBaseline libraries that normally handle asymmetric crypto.
TrafficAsymmetryRatioThreshold for client-heavy data sending vs server.