Listen to this Post
Introduction:
When a company entrusted with billions in UK government contracts—and already hit by a £100 million cyberattack—still fails basic security scans on its primary website and API endpoints, it signals systemic neglect, not isolated oversight. Capita plc’s repeated inability to implement fundamental protections like valid digital certificates, secure API headers, and hardened DNS configurations demonstrates a dangerous pattern that threat actors actively exploit for initial access and persistent compromise.
Learning Objectives:
- Detect and remediate common API security misconfigurations using free scanning tools.
- Perform DNS and certificate validation audits on public-facing assets.
- Harden Linux and Windows servers against the exact weaknesses observed in Capita’s infrastructure.
You Should Know:
- Automated Security Scanning – Finding What Capita Missed
Real-time scans of Capita’s domains revealed failing grades for basic security controls. You can replicate these checks on your own assets using open-source tools.
Step-by-step guide to scan a website and API for common misconfigurations:
On Linux (Kali/Ubuntu):
Install testssl.sh for certificate and SSL/TLS issues git clone https://github.com/drwetter/testssl.sh.git cd testssl.sh ./testssl.sh --ip one https://example.com Scan API endpoints for security headers and misconfigurations nikto -h https://api.example.com -ssl -Format html -o scan_report.html Check for exposed .git, .env, backup files gobuster dir -u https://example.com -w /usr/share/wordlists/dirb/common.txt -x .git,.env,.bak,.sql
On Windows (PowerShell with tools):
Invoke-WebRequest to check security headers $headers = Invoke-WebRequest -Uri "https://example.com" -Method Head $headers.Headers["Strict-Transport-Security"] $headers.Headers["Content-Security-Policy"] Use Invoke-Nmap (via WSL or native) for port scanning nmap -sV --script http-security-headers,ssl-enum-ciphers -p443 example.com
What this does: The first command runs a comprehensive SSL/TLS assessment (similar to Qualys SSL Labs). The second uses nikto to find misconfigured endpoints (like those Capita’s APIs likely exposed). The third brute-forces common sensitive file paths.
- Digital Certificate Validation – Spotting Recently Issued or Invalid Certs
Andy Jenkinson noted that an incorrect digital certificate was issued for a Capita subdomain just last week. Attackers use expired or self-signed certificates to intercept traffic or impersonate legitimate services.
Step-by-step certificate inspection:
Linux command to check certificate details:
Direct connection to check certificate chain openssl s_client -connect subdomain.capita.com:443 -servername subdomain.capita.com -showcerts | openssl x509 -text -noout Check certificate issuance date and issuer echo | openssl s_client -connect capita.com:443 2>/dev/null | openssl x509 -issuer -dates -subject
Windows PowerShell:
Get certificate from remote server
$cert = New-Object System.Net.Sockets.TcpClient('subdomain.capita.com', 443)
$stream = $cert.GetStream()
$ssl = New-Object System.Net.Security.SslStream($stream)
$ssl.AuthenticateAsClient('subdomain.capita.com')
$ssl.RemoteCertificate | Format-List
Check revocation status
certutil -verify -urlfetch $ssl.RemoteCertificate
Why this matters: Attackers can register spoofed domains with valid certificates if the organization fails to monitor its own certificate authorities. Regularly audit certificate issuance and expiration.
3. DNS Misconfigurations – The SolarWinds Lesson
The post reminds us of SolarWinds where a compromised subdomain gave attackers Domain Admin access. Capita’s “Not Secure” subdomains are ripe for takeover via dangling DNS records.
DNS enumeration and takeover testing:
Linux (using dnsrecon and subdomain enumeration):
Enumerate all DNS records for the domain dnsrecon -d capita.com -t axfr,zonewalk Find vulnerable subdomains pointing to decommissioned cloud services subfinder -d capita.com -silent | while read sub; do dig +short $sub | grep -E "cloudfront.net|azurewebsites.net|s3.amazonaws.com" done Check for CNAME takeover dig CNAME security.capita.com +short
Windows (using nslookup):
nslookup -type=NS capita.com nslookup -type=SOA capita.com for /f %i in (subdomains.txt) do nslookup %i.capita.com | find "NXDOMAIN"
Mitigation: Implement DNS security monitoring with tools like `dnsvalidator` and create automated alerts when subdomain records point to expired cloud resources.
- API Security Hardening – Preventing the Next Breach
Capita’s API endpoints received failing grades. Attackers exploit APIs through broken object level authorization (BOLA), excessive data exposure, and lack of rate limiting.
Step-by-step API security testing with Python and Burp Suite:
Install and run a basic API scanner:
On Linux, install Arjun for parameter discovery
pip3 install arjun
arjun -u https://api.capita.com/v1/users -o api_params.json
Test for mass assignment vulnerabilities
curl -X PUT https://api.capita.com/v1/user/12345 -H "Content-Type: application/json" -d '{"is_admin":true}'
Cloud hardening (Azure/AWS):
Check Azure API Management for missing OAuth az apim api show --resource-group capita-rg --service-name capita-api --api-id users --query "authenticationSettings" AWS API Gateway config review (no authentication) aws apigateway get-stages --rest-api-id abc123 --query "items[?methodSettings['/'].dataTraceEnabled==`true`]"
Fix misconfigurations: Enforce API keys, JWTs, and rate limiting. Use `modsecurity` on Linux or `RequestFiltering` on IIS to block malicious patterns.
- Continuous Compliance Monitoring – Why Fines Don’t Fix Negligence
The ICO reduced Capita’s fine from £45M to £15M after “fixes” were claimed, yet scans still fail. You need automated, daily compliance checks.
Set up automated security scanning with cron and scheduled tasks:
Linux cron for daily TLS scan:
crontab -e 0 6 /home/user/testssl.sh/testssl.sh --htmlfile /var/www/reports/capita_$(date +\%Y\%m\%d).html https://capita.com
Windows Task Scheduler with PowerShell:
Create a scheduled task to run Invoke-SecurityHeaders.ps1 daily $action = New-ScheduledTaskAction -Execute "PowerShell.exe" -Argument "-File C:\scripts\Check-APIHeaders.ps1" $trigger = New-ScheduledTaskTrigger -Daily -At 6am Register-ScheduledTask -TaskName "CapitaStyleAPICompliance" -Action $action -Trigger $trigger
Example Check-APIHeaders.ps1:
$urls = @("https://capita.com", "https://api.capita.com/v1/health")
foreach ($url in $urls) {
try {
$response = Invoke-WebRequest -Uri $url -Method Head -ErrorAction Stop
if (-not $response.Headers['X-Frame-Options']) {
Write-Warning "$url missing X-Frame-Options"
}
if (-not $response.Headers['Strict-Transport-Security']) {
Write-Warning "$url missing HSTS"
}
} catch {
Write-Error "$url failed: $_"
}
}
What Undercode Say:
- Key Takeaway 1: Regulatory fines do not guarantee improved security—only continuous automated validation and public transparency can hold vendors accountable.
- Key Takeaway 2: Basic misconfigurations (expired certs, missing headers, dangling DNS) remain the 1 initial access vector for major breaches, as seen with Capita, SolarWinds, and countless others.
Analysis: Capita’s case is a textbook example of “security theater”—claiming remediation while failing real-time scans. Organizations must shift from checkbox compliance to adversarial testing using tools like testssl.sh, subfinder, and Burp Suite. The persistence of “not secure” subdomains and invalid certificates indicates either gross incompetence or a deliberate bypass of security processes. For enterprises with government contracts, this level of negligence should trigger contract termination clauses. Threat actors actively scan for such low-hanging fruit, and the only defense is proactive, daily, and automated security validation across all assets.
Prediction:
If Capita does not immediately overhaul its security posture—including re-auditing all subdomains, rotating every certificate, and implementing real-time API security monitoring—it will suffer another catastrophic breach within 12 months. The UK government will likely begin excluding Capita from sensitive contracts, triggering a financial collapse similar to other outsourcers who failed basic security. Smaller competitors that adopt rigorous, automated security pipelines will win public sector trust and market share. Expect class-action lawsuits from the 6.6 million affected individuals, potentially reinstating the full £60M fine plus damages. The wider industry lesson: no amount of past revenue justifies ignoring foundational security hygiene.
▶️ Related Video (78% Match):
🎯Let’s Practice For Free:
IT/Security Reporter URL:
Reported By: Andy Jenkinson – Hackers Feeds
Extra Hub: Undercode MoN
Basic Verification: Pass ✅
