Windows File Access to Browser Credential Storage by Non-Browser Processes

Flags non-browser processes reading common browser credential storage files on Windows, indicating potential credential theft.

FreeReviewedSigma · Low · v2
Product
windows
Category
file_access
Author
frack113, X__Junior (Nextron Systems), Swachchhanda Shrawan Poudel (Nextron Systems), Parth-FourCore (SigmaHQ), DRL 1.1
Published
2025-05-22
Updated
2026-07-31

ATT&CK techniques

Cred Access → Discovery
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Defense Evasion

  8. Lateral Movement

  9. Collection

  10. C2

  11. Exfiltration

  12. Impact

What it detects

This rule flags Windows file access where the accessed path includes browser credential storage locations (such as Login Data, Cookies, EncryptedStorage, and related browser database files) combined with browser profile subpaths. It aims to identify attempts by non-browser processes to read sensitive browser data that attackers can use to obtain usernames, passwords, and session cookies. The detection relies on file_access telemetry including the accessed FileName and the creating process Image/ParentImage to distinguish likely non-browser access.

Related detections9 linkedT1555.003 — drag to rearrange
Malicious Qilin Chrome Credential Harvesting Script Execution via IPScanner (via process_creation)
Malicious Browser Credential Dump File Drop by Phantom Stealer via file_event
Suspicious Chromium Browser Launch with Remote Debugging Port for Cookie Theft (via process_creation)
Malicious dllFake Stealer Execution from WindowsApps Directory (via process_creation)
Malicious macOS Stealer Staging to Users Shared Directory (via process_creation)
Possible Spectre Ops C2 Beacon via nico and yfat Query Parameters via proxy
Suspicious Browser Kiosk Mode Forcing Credential Entry via process_creation
Malicious Live Ledger Stealer Execution via Ledger Lives Masquerade via process_creation
Suspicious Access to Chrome Encrypted Preference MAC Registry Values (via registry_set)
Windows File Access to Browser Credential Storage by Non-Browser Processes
Pivot detection · T1555.003 · 9 related

Changelog

v2
  1. v2
    Candidate ingested via manual entry.2026-07-31
  2. v1
    No changelog recorded for this version.2026-07-30

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