Suspicious Loopback Proxy Server Configured via Registry (via registry_set)

PremiumReviewedSigma · Medium · v1
Product
windows
Category
registry_set
Author
HuntRule
Published
2026-09-12
Updated
2026-09-12

ATT&CK techniques

Persistence → Defense Evasion
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Priv Esc

  6. Defense Evasion

  7. Cred Access

  8. Discovery

  9. Lateral Movement

  10. Collection

  11. C2

  12. Exfiltration

  13. Impact

What it detects

This rule detects modification of the Internet Settings ProxyServer value to a loopback address with proxy enable turned on which the CoralRaider malware uses to route victim browser traffic through a local interception proxy. Redirecting traffic to 127.0.0.1 enables credential and session theft and man-in-the-middle inspection of victim web activity.

Related detections9 linkedT1112 — drag to rearrange
Malicious WDigest Credential Caching Enabled via Registry (via registry_set)
Suspicious Remote Desktop Enabled via fDenyTSConnections Registry by Sandworm
Malicious Gh0stBins RAT Registry Marker HHClient
Suspicious PebbleDash C2 Configuration Stored Under WMI Security Key (via registry_set)
Suspicious WDigest UseLogonCredential Enablement for Plaintext Credential Theft (via registry_set)
PowerShell Storing an Encoded Payload in the Registry (via process_creation)
Malicious Impacket SMBexec Service Creation - Registry (via registry_event)
Malicious Microsoft Defender Tamper via Registry Modification
Malicious Impacket SMBexec Service Registration - Native (via security)
Suspicious Loopback Proxy Server Configured via Registry (via registry_set)
Pivot detection · T1112 · 9 related

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