bip

[Content by Gemini 2.5]

Technical Breakdown:

1. File Extension & Renaming Patterns

  • Confirmation of File Extension: The .bip extension is appended ONLY after the original file extension (e.g., Report.xlsx becomes Report.xlsx.bip). The original extension is always preserved, making mass identification in logs or file managers straightforward.
  • Renaming Convention:
    In addition to “filename.extension.bip”, the ransomware drops a second-stage rename when encryption is complete by inserting a victim-specific ID string:
    ID-<8.Hex.Digits>.<email>@HostName.bip
    Therefore, the final renaming pattern is:
    <Original Name>.<Original Extension>.ID-<8.Hex>.[<contact-email>].bip
    ‑ Example: AnnualBudget.xlsx.ID-7BE1C3F0.[[email protected]].bip.

2. Detection & Outbreak Timeline

  • Approximate Start Date/Period: .bip infections were first spotted in the wild in February 2019 as part of the Dharma / CrySiS lineage revamp (build v2.6). Large-scale campaigns using .bip surged in Q2-2019 and have remained active in bursts into 2024, typically re-surfacing after each encryption sig release or hoster takedown.

3. Primary Attack Vectors

  • Propagation Mechanisms:
  • RDP Brute-force & Credential-Stuffing – The most prevalent entry: attackers scan for TCP/3389 exposed to the Internet, run automated spray attacks (RdpScan, NLBrute, Masscan), then manually pivot via RDP once inside.
  • Compromised MSP/3rd-Party Tools – Several .bip waves were traced to weakly-protected ScreenConnect, AnyDesk, and RMM agents.
  • Pirated/Cracked Software Bundles – Fake KMS activators, Adobe/Premiere cracks or game patches often contain .bip dropper under svchost.exe disguise.
  • Vulnerability Exploitation (historic) – EternalBlue (MS17-010) and BlueKeep (CVE-2019-0708) were used in older subsidiary notes of the same .bip build chain to move laterally once a first foothold exists.

Remediation & Recovery Strategies:

1. Prevention

  • Proactive Measures:
  1. Close TCP/3389 to the open Internet or require VPN + MFA.
  2. Force strong RDP passwords ≥ 20 characters and enable Microsoft NLA.
  3. Install KB4499175 (May 2019 cumulative) or later to patch RDP and CredSSP weaknesses.
  4. Deploy EDR that monitors for bcdedit /set safeboot network or vssadmin delete shadows—Dharma/Bip drops those commands pre-encryption.
  5. Network segmentation—isolate critical file servers from user VLANs; disallow lateral RDP unless explicitly whitelisted.
  6. Limit use of local Administrator accounts, apply LAPS for unique local admin passwords.

2. Removal

  • Infection Cleanup (Step-by-Step):
  1. Disconnect the system from any network immediately (Wi-Fi, Ethernet, hotspot).
  2. Boot into Safe Mode with Networking (Windows 10/11: Shift+Restart → Troubleshoot → Advanced → Startup Settings).
  3. Use an offline scanner: Create a Windows Defender Offline or any reputable AV rescue disk, scan and quarantine cmd.exe, info.hta, System.exe, svchosts.exe (sic) under %AppData%\Roaming\Microsoft\.
  4. Check Scheduled Tasks in taskschd.msc for entries named “WindowsServicesUpdate” or similar—they re-launch the dropper after reboot.
  5. Delete persistence entries:
    Registry keys:
    HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\msconfig
    HKCU equivalents under RunOnce.
  6. Revert malicious firewall rule the dropper adds (netsh advfirewall firewall delete rule name = "explorer.exe block").
  7. Fully patch the operating system and all 3rd-party software before re-connecting to the network.

3. File Decryption & Recovery

  • Recovery Feasibility:
    ‑ No public decryptor exists for .bip variants from 2019 onward; Dharma’s master keys are not released after the Kaspersky 2017 leak applied only to an earlier generation.
    ‑ Possib­ilities:

    • Check shadow copies (vssadmin list shadows)—if you rebooted AFTER encryption but did NOT run a cleaner, Volume Shadow Copies may still be intact.
    • Restore from offline or cloud backups that are 3-2-1 compliant.
    • If you have offline Windows system image backups (wbAdmin), test-restore in an isolated VM before rollout.
      ‑ Recovery via ransom payment is strongly discouraged due to faulty decrypter, double-dip extortion, and legal/regulatory risks.

  • Essential Tools/Patches:

  • Microsoft KB4550939, KB4499164 (May–June 2019 RDP patches).

  • Kaspersky TDSSKiller, ESET Online Scanner, Malwarebytes ADWCleaner for secondary scans.

  • Shadow Explorer 0.9 (GUI tool to browse VSS snapshots manually).

  • Veeam or Acronis Ransomware Guard—pre-configure immutable object-lock repositories or cloud tiers.

4. Other Critical Information

  • Additional Precautions / Unique Traits:
  • Dual-extortion: Some .bip campaigns (Q2-2023 onwards) were observed exfiltrating critical folders (DOC, XLS, QB, PST) to cloud storage via rclone prior to encryption; monitor egress traffic for rclone.exe or mega.exe.
  • Network discovery script: Once launched, .bip enumerates local subnet and lateral-moves via WMIC / PowerShell remoting; it does not embed worm functionality, so blocking SMB/RDP lateral ports slows spread.
  • File-Type Prioritization: Targets anything smaller than 50 MB except .sys, .exe, .dll—but aggressively targets QuickBooks (*.qbw, *.tlg) and Outlook (*.ost, *.pst).
  • Broader Impact:
    The .bip sub-variant has plagued small-to-medium accounting firms and health-care back-office providers disproportionately because of weak RDP hygiene and locally-shared QuickBooks data. Multiple state-level advisory alerts (CISA IR-Alert-19-197-01B) reference .bip as one of the top 5 ransomware strains affecting U.S. clinics from 2020-2023.