13 KiB
Simulated Incident Response Exercise
Brute-Force Attack → Login API → Data Breach (Ghaymah Cloud)
Scenario disclaimer: This is a hypothetical, simulated exercise written for exam/training purposes. It does not claim that an actual breach occurred at Ghaymah — it's a realistic case study built on Ghaymah's publicly known architecture (Git-push container deployment, managed Kubernetes, managed PostgreSQL, a customer-facing Login API/dashboard) as identified in Part 1 of this audit.
PART 1 — Step-by-Step Attack Analysis
Mapped loosely to the Cyber Kill Chain and MITRE ATT&CK, so each step has a defensive framework you can cite in your exam.
| Step | What Happens | ATT&CK Technique |
|---|---|---|
| 1. Reconnaissance | Attacker identifies the Login API endpoint (e.g. via the dashboard's client-side JS bundle, API docs, or simply deploy.ghaymah.systems/login) and fingerprints response behavior — does it return different errors for "user not found" vs "wrong password"? Does it rate-limit? |
T1595 – Active Scanning |
| 2. Credential Sourcing | Attacker uses either (a) a common-password/dictionary list (classic brute force), or (b) a leaked-credential list from unrelated past breaches (credential stuffing — more realistic and dangerous, since it exploits password reuse rather than weak passwords) | T1110.004 – Credential Stuffing |
| 3. Execution / Delivery | Automated tooling submits authentication requests at scale, rotating through a proxy/residential-IP pool or botnet specifically to evade simple per-IP rate limiting | T1110 – Brute Force |
| 4. Detection Gap (root cause) | The Login API has no effective rate limiting, no account lockout, no CAPTCHA challenge, and no anomaly alerting on failed-login volume — this is the actual vulnerability, not the attacker's sophistication | — |
| 5. Initial Access | One or more valid credential pairs succeed. Attacker receives a valid session token / JWT | T1078 – Valid Accounts |
| 6. Discovery | Using the legitimate session, attacker enumerates what the compromised account can reach: deployed apps, environment variables/secrets, connected managed database, container registry, API keys/CLI tokens | T1087 / T1526 – Account & Cloud Service Discovery |
| 7. Collection & Exfiltration | Attacker downloads environment variables (which commonly hold DB credentials, third-party API keys), or directly queries the connected managed PostgreSQL instance, and exfiltrates the data out over normal HTTPS (blends into legitimate traffic) | T1552 – Unsecured Credentials; T1567 – Exfiltration Over Web Service |
| 8. Impact | Confidentiality breach of customer data; potential secondary compromise if exfiltrated API keys/DB credentials are reused elsewhere; reputational and (if PII involved) regulatory impact | — |
Key takeaway for the analysis section: the breach didn't require a sophisticated exploit — it required the absence of three basic controls: rate limiting, lockout/backoff, and detection. That's the through-line into the rest of this exercise.
PART 2 — Incident Response Plan
Structured on the NIST SP 800-61 lifecycle (Preparation → Detection & Analysis → Containment → Eradication → Recovery → Post-Incident Activity), scoped to this specific scenario.
2.1 Preparation (what should already exist before this happens)
- A named Incident Response team with clear roles: Incident Commander, Security Analyst (Investigation), Engineering Lead (Containment), Communications/Legal (customer & regulatory notification)
- Centralized authentication logs (failed + successful logins, source IP, user-agent, timestamps) retained and searchable
- A pre-approved playbook for "credential compromise" so responders aren't improvising during the incident
- Pre-established communication channels (on-call paging, incident Slack/War-room channel)
2.2 Detection & Analysis
- Alert fires (see Part 4 rule design) — e.g. "50+ failed logins for account X across 6 IPs in 10 minutes, followed by a successful login."
- Analyst triages: confirm it's not a false positive (e.g. legitimate user with a broken password manager).
- Determine scope: which account(s) compromised, what that account could access (apps, DB, secrets, registry), whether data was actually accessed/exfiltrated (check access/query logs, egress volume).
- Classify severity (e.g. Sev-1 if customer data confirmed exfiltrated; Sev-2 if account compromised but no confirmed data access).
2.3 Containment
Short-term (minutes):
- Force-revoke all active sessions/tokens for the compromised account
- Lock the account and require identity-verified password reset
- Temporarily rate-limit or block the source IP(s)/ranges involved
Longer-term (hours):
- Rotate any secrets/API keys/DB credentials the compromised account had access to (assume anything reachable was seen)
- Review and, if needed, temporarily restrict the Login API more broadly (e.g. tighten rate limits platform-wide) while the root cause is patched
2.4 Eradication
- Confirm no persistence mechanism was planted (e.g. a newly-added API token, SSH key, or webhook the attacker created for continued access) — check the account's audit log of created credentials/tokens during the compromise window, and revoke anything created that the legitimate user didn't authorize
- Patch the actual gap: deploy rate limiting/lockout on the Login API (see Part 3)
2.5 Recovery
- Restore the account to the legitimate user with new credentials + mandatory MFA enrollment
- Monitor the account and related infrastructure closely for a defined period (e.g. 30 days) for signs of reoccurrence
- Gradually lift any emergency-tightened rate limits once confidence in the fix is established
2.6 Post-Incident Activity
- Blameless post-mortem: root cause (missing rate limiting/lockout/alerting), timeline, what worked, what didn't
- Update the IR playbook and detection rules based on lessons learned
- Customer/regulatory notification: if this were real and PII was exposed, this is where Ghaymah's stated "prompt notification" commitment (from their
/securitypage) would be executed — legal/comms determines notification obligations based on applicable law (e.g. GDPR-style breach notification timelines if EU data subjects are involved)
PART 3 — Prevention
3.1 Network Policies
- Rate limiting at the API gateway/edge: cap login attempts per IP and per account (e.g. via the WAF Ghaymah already advertises on their
/securitypage) - Progressive backoff / account lockout: exponentially increasing delay after repeated failures, temporary lockout after a threshold, with self-service unlock via email verification (avoids permanent denial-of-service against the legitimate user)
- CAPTCHA/challenge triggered after N failed attempts, before further attempts are accepted
- IP reputation / bot-mitigation filtering on the login endpoint specifically (block known malicious ranges, Tor exit nodes, datacenter-IP traffic patterns inconsistent with normal user logins)
- Kubernetes NetworkPolicies (default-deny egress/ingress between tenant namespaces): even if one customer's account is compromised, this limits how far an attacker can move laterally toward other tenants' workloads or Ghaymah's internal control-plane services
- mTLS / private networking for internal service-to-service and admin APIs, so a compromised customer-facing credential can't be leveraged to reach internal management interfaces
3.2 Container Security
- Secrets management: never bake DB credentials/API keys into container images or plaintext env vars long-term — use a secrets manager (e.g. Vault-style short-lived, auto-rotating credentials) so a leaked env-var dump has a short shelf life
- Least-privilege service accounts: each deployed container/pod gets only the RBAC permissions it needs — no default cluster-admin, no broad service-account tokens mounted unnecessarily
- Image scanning in the CI/CD pipeline: block deployment of images with known-critical CVEs (relevant given Ghaymah's "push Git → auto-build" pipeline runs customer code automatically)
- Runtime security monitoring (e.g. Falco-style tooling) to detect anomalous in-container behavior post-compromise (unexpected process execution, outbound connections to new destinations)
- Read-only root filesystems and dropped Linux capabilities by default, reducing what an attacker can do even with container-level access
- Automatic credential rotation tied to security events — if an account tied to a deployment is flagged compromised, auto-rotate that deployment's DB credentials and registry tokens rather than waiting for manual response
3.3 Identity Hardening (closes the loop back to Part 1's IAM findings)
- Enforce MFA for account logins and, ideally, for CLI/API token generation
- Strong password hashing (Argon2id or bcrypt with an appropriate cost factor) so even a full DB compromise doesn't yield plaintext-equivalent credentials
- Breached-password checking at signup/reset time (reject passwords found in known-breach corpora)
- Short-lived sessions + refresh token rotation, so a stolen token has a limited window of usefulness
PART 4 — Alert Rule Design
Two versions: a vendor-agnostic Sigma rule (the standard portable format security teams use across SIEMs) and a Prometheus/Alertmanager rule, since Ghaymah's stack is Kubernetes-based and likely already emits Prometheus-style metrics.
4.1 Sigma Detection Rule
title: Brute Force / Credential Stuffing Attempt on Login API
id: 7e4b1a2c-91f3-4d6e-8a2b-6c1f9e0d3a55
status: experimental
description: >
Detects a high volume of failed authentication attempts against the
Login API, either concentrated from a single source (classic brute
force) or spread across many sources against a single account
(credential stuffing).
references:
- https://attack.mitre.org/techniques/T1110/
logsource:
category: application
product: ghaymah-login-api
detection:
failed_by_ip:
event_type: "authentication_failure"
cond_ip:
failed_by_ip | count(by: source_ip) > 10
timeframe: 5m
failed_by_account:
event_type: "authentication_failure"
cond_account:
failed_by_account | count(by: username, distinct: source_ip) > 5
timeframe: 10m
condition: cond_ip or cond_account
level: high
tags:
- attack.credential_access
- attack.t1110
- attack.t1110.004
falsepositives:
- Misconfigured client/app repeatedly retrying with a stale credential
- Legitimate user with a broken password manager
4.2 Prometheus / Alertmanager Rule (metric-based, fits a K8s-native stack)
groups:
- name: login-api-brute-force
rules:
- alert: LoginAPIBruteForceByIP
expr: sum(rate(login_failures_total[5m])) by (source_ip) > 10
for: 1m
labels:
severity: high
annotations:
summary: "Possible brute-force attack from {{ $labels.source_ip }}"
description: "More than 10 failed logins/5m from a single IP against the Login API."
- alert: LoginAPICredentialStuffingByAccount
expr: sum(count without (source_ip) (login_failures_total)) by (username) > 5
and count(count by (username, source_ip)(login_failures_total)) by (username) > 3
for: 2m
labels:
severity: high
annotations:
summary: "Possible credential-stuffing attempt against account {{ $labels.username }}"
description: "5+ failed logins for one account from 3+ distinct source IPs within the window."
- alert: LoginSuccessAfterFailureBurst
expr: increase(login_success_total[1m]) > 0
and increase(login_failures_total[10m]) > 5
for: 0m
labels:
severity: critical
annotations:
summary: "Successful login immediately follows a failure burst - possible account takeover"
description: "Treat as high-risk: consider forcing step-up MFA or session re-verification."
4.3 Recommended Automated Response (tied to the alerts above)
LoginAPIBruteForceByIP→ auto-block the source IP at the WAF/edge for a cooldown period (e.g. 30 min) + notify SOCLoginAPICredentialStuffingByAccount→ force account lockout + require password reset + notify the account owner by emailLoginSuccessAfterFailureBurst→ don't auto-block (avoid locking out the legitimate user who just succeeded), but flag the session as high-risk: require step-up MFA re-verification and alert SOC for manual review
Summary
The scenario's real lesson: the technical attack (brute force / credential stuffing) is unsophisticated and well-understood — what determines whether it becomes a breach is whether basic controls (rate limiting, lockout, MFA, alerting) exist on the Login API. The IR plan, prevention controls, and alert rules above form a closed loop: prevent the easy cases, detect what gets through, and respond fast enough to limit blast radius when it does.