CVE-2020-36239

What is this vulnerability?

CVE-2020-36239 is categorized as a critical Missing Authorization flaw with a CVSS base score of 9.8. Based on our vulnerability intelligence, this issue occurs when the application fails to securely handle untrusted data boundaries.

Jira Data Center, Jira Core Data Center, Jira Software Data Center from version 6.3.0 before 8.5.16, from 8.6.0 before 8.13.8, from 8.14.0 before 8.17.0 and Jira Service Management Data Center from version 2.0.2 before 4.5.16, from version 4.6.0 before 4.13.8, and from version 4.14.0 before 4.17.0 exposed a Ehcache RMI network service which attackers, who can connect to the service, on port 40001 and potentially 40011[0][1], could execute arbitrary code of their choice in Jira through deserialization due to a missing authentication vulnerability. While Atlassian strongly suggests restricting access to the Ehcache ports to only Data Center instances, fixed versions of Jira will now require a shared secret in order to allow access to the Ehcache service. [0] In Jira Data Center, Jira Core Data Center, and Jira Software Data Center versions prior to 7.13.1, the Ehcache object port can be randomly allocated. [1] In Jira Service Management Data Center versions prior to 3.16.1, the Ehcache object port can be randomly allocated.

This architectural defect enables adversaries to bypass intended security controls, directly manipulating the application's execution state or data layer. Immediate strategic intervention is required.

Risk Assessment

Impact on Systems

✅ Unauthorized Data Access: Attackers can bypass authorization controls to access other users' data or administrative endpoints.

✅ Account Takeover: Broken authentication or authorization may enable full account compromise without valid credentials.

✅ API Abuse: Exploiting this vulnerability enables mass data harvesting or destructive operations through unprotected API endpoints.

How to Fix and Mitigate CVE-2020-36239

1. Apply Vendor Patches: Upgrade affected components to their latest, non-vulnerable versions immediately.
2. Implement Input Validation: Ensure all user-supplied data is validated, sanitized, and type-checked before processing.
3. Deploy Runtime Protection: Use Precogs continuous monitoring to detect exploitation attempts in real time.
4. Audit Dependencies: Review and update all third-party libraries and transitive dependencies.

Defending with Precogs AI

Precogs API Security Engine performs deep analysis of API endpoints using Code Property Graph traversal, detecting broken authentication, mass assignment, BOLA/IDOR, and SSRF vulnerabilities across REST, GraphQL, and gRPC interfaces before they reach production.

Use Precogs to continuously scan your codebase, binaries, APIs, and infrastructure for this vulnerability class and related attack patterns. Our AI-powered detection engine combines static analysis with threat intelligence to identify exploitable weaknesses before attackers do.

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Vulnerability Code Signature

Attack Data Flow

Vulnerable Code Pattern

// ❌ VULNERABLE: Missing Authorization (BOLA)
app.get('/api/users/:id/data', async (req, res) => {
  const userId = req.params.id;
  // Taint sink: fetches data for requested ID without verifying ownership
  const data = await db.getUserData(userId);
  res.json(data);
});

Secure Code Pattern

// ✅ SECURE: Strict Resource Authorization
app.get('/api/users/:id/data', requireAuth, async (req, res) => {
  const requestedId = req.params.id;
  const authenticatedId = req.user.id;
  
  // Sanitized validation: check ownership
  if (requestedId !== authenticatedId && !req.user.isAdmin) {
    return res.status(403).json({ error: "Unauthorized access" });
  }
  
  const data = await db.getUserData(requestedId);
  res.json(data);
});

How Precogs Detects This

Precogs API Security Engine comprehensively audits all exposed endpoints to guarantee strict session validation and resource authorization.