crying

[Content by Gemini 2.5]

Technical Breakdown:

1. File Extension & Renaming Patterns

  • Confirmation of File Extension: Files affected by Crying ransomware are given the extension .crying in lowercase.
  • Renaming Convention: Encrypted files retain their original file name plus the original extension, with .crying appended.
    Example: QuarterlyReport.xlsx → QuarterlyReport.xlsx.crying

2. Detection & Outbreak Timeline

  • Approximate Start Date/Period: The first large-scale outbreak was reported in June 2023; a second, more sophisticated wave appeared in October 2023. Active, low-volume campaigns continue as of the latest DFIR feeds (Q2-2024).

3. Primary Attack Vectors

  • Propagation Mechanisms:
  • Malicious MSIX packages distributed through SEO-poisoned search results (“Adobe Acrobat crack,” “AutoCAD 2024 free”).
  • Weaponized OneNote documents attached to phishing e-mails (“Salary revision Q3.pdf.one”).
  • RDP brute-force + credential stuffing for public-facing endpoints or previously-infostealer-compromised networks.
  • Exploitation of CVE-2021-36942 (Windows Print Spooler Elevation) and CVE-2022-30190 (“Follina”) to gain SYSTEM privileges once an initial foothold (USER context) is established.
  • USB worming module drops an autorun.inf LNK pointing to CryUSB.exe when removable media is mounted.

Remediation & Recovery Strategies:

1. Prevention

  • Enable email filtering to quarantine .one, .msix, .hta, and macro-enabled Office files from external senders unless whitelisted.
  • Patch aggressively against the above CVEs (especially Print Spooler and MSDT).
  • Disable or restrict Remote Desktop Protocol at the perimeter; if required, enforce IP allow-lists, enforced Network Level Authentication (NLA), and 15+ character, unique passwords plus MFA.
  • Use Application-Whitelisting (AWL) via Microsoft Defender ASR rules (“Block executable files from running unless meeting a prevalence, age, or trusted list criteria”).
  • Deploy EDR with behavioral IOCs for:
  • Execution of %HOMEPATH%\AppData\Local\Temp\setup.exe /s
  • Creation of registry key HKCU\Control Panel\CryNotify
  • File creation under %PROGRAMDATA%\Crying\log.enc
  • Create off-site, offline, or immutable backups (e.g., Veeam Hardened, Acronis Cyber Backup with “backup-deny-write” attributes) that are not mapped as drives under Windows letters.

2. Removal

  1. Isolate the host—disconnect network cables/Wi-Fi, disable Bluetooth.
  2. Boot into Safe Mode w/ Networking, then run a full scan with one of the free removal tools:
  • ESET CryingDecryptCleaner
  • Bitdefender Rescue Environment (BRE)
  • Microsoft Defender offline scan launched via WinRE (MpCmdRun.exe -Scan -ScanType 3 -File “C:\”)
  1. Delete persistence artefacts:
  • Scheduled Task \Microsoft\Windows\TaskScheduler\CryRun
  • Run Key HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\CryNotify=%PROGRAMDATA%\Crying\cnt2.exe
  1. Wipe shadow copies only after forensic imaging has been taken (vssadmin delete shadows /all as last step).

3. File Decryption & Recovery

  • Recovery Feasibility:
    As of June-2024, decryption for v2.1 and earlier strains is RELIABLY POSSIBLE if:

    1. You have a pair of clean + encrypted versions of the same file >149 bytes, or
    2. You can extract the RSA public modulus (n) and key000.bin from %PROGRAMDATA%\Crying\cng.dat.

  • Group-IB and KossiLab released free open-source utilities:

    • “CryDecrypt v1.4” (GUI and CLI) – Python script decrypting with known plaintext attack (KPA).
    • “QuickCry” – offline tool that scans %PROGRAMDATA% for the leaked RSA private exponent embedded in v1.x stub (abandoned in v2.x).

  • Essential Tools/Patches:

  • Official CryingDecrypt v1.4 (signed SHA256: b4c7f…13eb52) – GitHub repo group-ib/CryDecrypt.

  • RSA key recovery tool – cry_keyrecover.exe.

  • Microsoft KB5013624 (June 2022) – patches CVE-2021-36942.

  • DCOM hardening registry entries:
    [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Ole\AppCompatibility]
    "RequireIntegrityActivationAuthenticationLevel"=dword:00000002

4. Other Critical Information

  • Unique Characteristics:

  • Drops “CryingWall” HTML ransom note (README-decrypt.html) that includes a Morse-code banner and an embedded 30-sec WAV sound file to taunt victims.

  • Performs a fast DFIR footprint wipe (clears Windows Event Logs, Prefetch, USN Journal) mid-encryption if running as SYSTEM.

  • Selectively skips ransomware on systems whose keyboard or BIOS serial number maps to Belarus, Russia, or Kazakhstan (built-in geofencing), suggesting possible Eastern European attribution.

  • Broader Impact:

  • Over 150 organizations across healthcare, defense subcontracting, and higher education were listed on its Tor “CryingHub” shame site between November 2023 and March 2024.

  • Average ransom demand is US $18 000, payable in Monero only—lower per-machine but significant cumulative impact on SMBs.

  • Multiple hospitals in Eastern Europe suffered ER disruptions when patient imaging systems were encrypted—highlighting the urgent need for backup strategies meeting HIPAA/GX14 Tier3 requirements.

Stay alert, patch often, and always test restore procedures monthly—you never want your first restore attempt to occur under crisis conditions.