Google DeepMind AI Lowers RSA-1024 Cracking Barrier: Defending Legacy Infrastructure

---
title: TLS Connection Using RSA-1024 Certificate
description: Detects TLS handshakes where the server certificate uses an RSA key size of 1024 bits or less, indicating vulnerability to AI-accelerated factoring attacks.
author: Security Arsenal
date: 2026/01/15
logsource:
  category: network_connection
  product: zeek
detection:
  selection:
    - ssl.version|contains: 'TLS'
      ssl.subject|contains: 'CN='
      ssl.server_name|re: '.+'
    - ssl.key_length: 1024
    - ssl.key_length: 512
  condition: selection
falsepositives:
  - Legacy internal services with outdated certificates
  - Embedded systems with hardcoded cryptographic constraints
level: high
---
title: SSH RSA-1024 Key Exchange
description: Identifies SSH connections negotiating weak RSA host keys or user authentication keys vulnerable to AI-optimized cryptanalysis.
author: Security Arsenal
date: 2026/01/15
logsource:
  category: network_connection
  product: zeek
detection:
  selection:
    ssh.auth.success: true
    ssh.server.host_key|contains: 'ssh-rsa'
  filter_weak:
    ssh.server.host_key_bits: 1024
  condition: selection and filter_weak
falsepositives:
  - Legacy network devices and management interfaces
  - Industrial control systems with deprecated firmware
level: critical
---
title: OpenSSL or LibreSSL Generating RSA-1024 Keys
description: Detects local generation of weak RSA keys on endpoints or servers, indicating potential policy violations or legacy application requirements.
author: Security Arsenal
date: 2026/01/15
logsource:
  category: process_creation
  product: linux
detection:
  selection:
    Image|endswith:
      - '/openssl'
      - '/libressl'
    CommandLine|contains:
      - 'genrsa'
      - 'req'
      - 'x509'
    CommandLine|contains:
      - '1024'
      - '512'
  condition: selection
falsepositives:
  - Legacy PKI maintenance operations
  - Testing environments (should still be flagged)
level: medium

// Hunt for RSA-1024 usage in TLS certificates and SSH connections
let WeakKeySizes = dynamic([1024, 512]);
union isfuzzy=true
    (CommonSecurityLog
    | where DeviceVendor =~ "Zeek" or DeviceVendor =~ "Suricata"
    | where AdditionalExtensions has "key_length"
    | extend KeyLength = toint(extract(@"key_length=(\d+)", 1, AdditionalExtensions))
    | where KeyLength in (WeakKeySizes)
    | project TimeGenerated, SourceIP, DestinationIP, DestinationPort, KeyLength, AdditionalExtensions),
    (DeviceNetworkEvents
    | where RemotePort in (443, 22, 993, 995)
    | where InitiatingProcessFileName in~ ("openssl", "ssh", "putty.exe", "winscp.exe")
    | project TimeGenerated, DeviceName, RemoteIP, RemotePort, InitiatingProcessFileName),
    (SecurityEvent
    | where EventID == 4688
    | where CommandLine has_any ("openssl", "ssh-keygen", "puttygen")
    | where CommandLine has_any ("1024", "512")
    | project TimeGenerated, Computer, Account, CommandLine)
| summarize WeakCryptoEvents = count(), FirstSeen = min(TimeGenerated), LastSeen = max(TimeGenerated) by SourceIP, DestinationIP, KeyLength
| where WeakCryptoEvents > 0
| sort by LastSeen desc

-- Hunt for RSA-1024 keys and weak certificate files on endpoints
SELECT FullPath, Size, Mtime, 
       parse_pem(file=FullPath) AS Certificate,
       process_tracker(pid=process_pid).Exe AS ProcessUsingKey
FROM glob(globs=[
    "C:\\**\\*.key",
    "C:\\**\\*.pem", 
    "C:\\**\\*.crt",
    "/etc/ssl/private/*.key",
    "/home/*/.ssh/id_rsa",
    "/root/.ssh/id_rsa"
])
WHERE 
    -- Check for RSA-1024 indicators in file content or metadata
    (Certificate.PublicKey.RSA.BitLength <= 1024)
    OR (FullPath =~ "1024")
    OR (Size < 2000 AND FullPath =~ "\\.key$")  -- Heuristic: RSA-1024 private keys are typically < 2KB
    OR (ProcessUsingKey =~ "openssl|ssh|gpg")
ORDER BY Mtime DESC

# RSA-1024 Cryptographic Audit and Remediation Script
# Run as Administrator on Windows systems

$ReportPath = "C:\SecurityAudit_RSA1024_$(Get-Date -Format 'yyyyMMdd_HHmmss').csv"
$WeakCerts = @()

Write-Host "[*] Auditing Local Machine Certificate Stores for RSA-1024..." -ForegroundColor Cyan

# Check all certificate stores for weak RSA keys
$Stores = @("Cert:\LocalMachine\My", "Cert:\LocalMachine\Root", "Cert:\LocalMachine\CA", "Cert:\CurrentUser\My")

foreach ($Store in $Stores) {
    if (Test-Path $Store) {
        $Certs = Get-ChildItem -Path $Store -Recurse | Where-Object {$_.PublicKey.Key -is [System.Security.Cryptography.RSACryptoServiceProvider]}
        foreach ($Cert in $Certs) {
            $KeySize = $Cert.PublicKey.Key.KeySize
            if ($KeySize -le 1024) {
                $WeakCerts += [PSCustomObject]@{
                    Store = $Store
                    Subject = $Cert.Subject
                    Issuer = $Cert.Issuer
                    Thumbprint = $Cert.Thumbprint
                    KeySize = $KeySize
                    NotAfter = $Cert.NotAfter
                    NotBefore = $Cert.NotBefore
                    HasPrivateKey = $Cert.HasPrivateKey
                }
                Write-Warning "Weak certificate found: $($Cert.Subject) (Key Size: $KeySize)"
            }
        }
    }
}

# Check TLS registry settings for weak cipher suites
Write-Host "[*] Checking TLS Registry Configuration..." -ForegroundColor Cyan
$TLSPaths = @(
    "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.0\Server",
    "HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.1\Server"
)

foreach ($Path in $TLSPaths) {
    if (Test-Path $Path) {
        $Enabled = Get-ItemProperty -Path $Path -Name "Enabled" -ErrorAction SilentlyContinue
        if ($Enabled.Enabled -eq 1) {
            Write-Warning "Weak TLS protocol enabled: $Path"
        }
    }
}

# Check for OpenSSH weak keys (if installed)
if (Get-Service sshd -ErrorAction SilentlyContinue) {
    Write-Host "[*] Auditing OpenSSH Host Keys..." -ForegroundColor Cyan
    $SSHKeys = Get-ChildItem "C:\ProgramData\ssh\ssh_host_*_key.pub" -ErrorAction SilentlyContinue
    foreach ($KeyFile in $SSHKeys) {
        $KeyContent = Get-Content $KeyFile.FullName -Raw
        if ($KeyContent -match "ssh-rsa") {
            $KeyParts = $KeyContent -split " "
            $KeyBytes = [Convert]::FromBase64String($KeyParts[1])
            # Rough estimation: RSA-1024 keys are ~148 bytes in SSH format
            if ($KeyBytes.Length -lt 200) {
                Write-Warning "Potential weak SSH host key: $($KeyFile.Name)"
            }
        }
    }
}

# Export results
if ($WeakCerts.Count -gt 0) {
    $WeakCerts | Export-Csv -Path $ReportPath -NoTypeInformation
    Write-Host "[!] Found $($WeakCerts.Count) weak certificates. Report saved to: $ReportPath" -ForegroundColor Red
} else {
    Write-Host "[+] No RSA-1024 certificates found in audited stores." -ForegroundColor Green
}

# Remediation recommendations
Write-Host "`n[*] Remediation Actions Required:" -ForegroundColor Yellow
Write-Host "1. Revoke and reissue certificates with RSA-2048 or ECDSA P-256 minimum"
Write-Host "2. Update TLS configuration to disable TLS 1.0/1.1"
Write-Host "3. Rotate SSH host keys to Ed25519 or RSA-3072"
Write-Host "4. Audit HSM configurations for legacy key sizes"

# Check for pending certificate auto-enrollment issues
$CertReq = Get-ChildItem "Cert:\LocalMachine\Request" -ErrorAction SilentlyContinue
if ($CertReq) {
    Write-Host "[!] Pending certificate requests detected - verify they request adequate key sizes" -ForegroundColor Magenta
}