Suspicious Phishing URL with Unrendered Template Placeholder (via proxy)

ATT&CK techniques

Initial Access

Recon
Resource Dev
Initial Access
- T1566.002Spearphishing Link
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects web requests whose URL path contains the unrendered phishing-kit template placeholder sf_rand_string_lowercase6, a literal artifact left in links from a large refresh-header phishing campaign. The presence of this build-time placeholder in a live URL is a strong indicator of the credential-harvesting kit and its automatic redirect landing pages.

Reporting behind it

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Suspicious Phishing URL with Unrendered Template Placeholder (via proxy)

Pivot detection · T1566.002 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

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