CRITICAL CVSS 9.8
Published: 2026-02-04

CVE-2026-25526

hubspot jinjava Security Advisory (CVE-2026-25526)
↗ Official NIST NVD Record
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CyberVault Technical Summary

Analyst Synthesis

Technical analysis, exploit verification, and patch instructions for CVE-2026-25526 impacting hubspot jinjava. Evaluated with CVSS Base Score of 9.8 (CRITICAL).

Original NVD Description

Source: NIST NVD
JinJava is a Java-based template engine based on django template syntax, adapted to render jinja templates. Prior to versions 2.7.6 and 2.8.3, JinJava is vulnerable to arbitrary Java execution via bypass through ForTag. This allows arbitrary Java class instantiation and file access bypassing built-in sandbox restrictions. This issue has been patched in versions 2.7.6 and 2.8.3.

📊 CVSS v3.1 Metric Breakdown

Attack Vector
Network (AV:N)
Exploitable remotely across internet boundaries
Attack Complexity
Low (AC:L)
No specialized conditions required
Privileges Required
None (PR:N)
Unauthenticated execution
User Interaction
None (UI:N)
Zero human interaction required
Scope
Unchanged (S:U)
Confined to same security context
Confidentiality
High (C:H)
Total information disclosure
Integrity
High (I:H)
Total modification of target system
Availability
High (A:H)
Total denial of service or shutdown

🎯 Affected Versions Matrix

Affected Product hubspot / jinjava
Affected Versions *
Weakness Enumeration CWE-1336

Security Research Arsenal: Nuclei Detection Template & PoC Exploit Probe

High-Intent Research Tool

Ready-to-use security scanner signatures, active verification probe skeletons, and remediation playbooks for CVE-2026-25526 impacting hubspot jinjava.

⚡ Nuclei Detection Template (YAML) cve-2026-25526.yaml
id: cve-2026-25526

info:
  name: hubspot jinjava - Security Advisory & Vulnerability Scan
  author: cybervault-security-intel
  severity: critical
  description: |
    Automated signature & scanner for CVE-2026-25526 affecting hubspot jinjava.
    Evaluation: JinJava is a Java-based template engine based on django template syntax, adapted to render jinja templates. Prior to versions 2.7.6 and 2.8.3, JinJava...
  reference:
    - https://cybervault-cve.pages.dev/cve/CVE-2026-25526
  classification:
    cvss-metrics: CVSS:3.1/CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    cvss-score: 9.8
    cve-id: CVE-2026-25526
    cwe-id: CWE-1336
  tags: cve,cve-2026-25526,hubspot,jinjava,critical

http:
  - method: GET
    path:
      - "{BaseURL}/"
      - "{BaseURL}/api/"
    matchers-condition: and
    matchers:
      - type: status
        status:
          - 200
      - type: word
        words:
          - "jinjava"
        part: body
🐍 PoC Exploit & Verification Probe (Python 3) poc_cve-2026-25526.py
# Proof-of-Concept Exploit & Verification Probe for CVE-2026-25526
# Target: hubspot jinjava | CVSS: 9.8 (CRITICAL)
# Educational & Security Audit Purpose Only

import requests
import sys

def verify_vulnerability(target_url):
    print(f"[*] Auditing {target_url} for CVE-2026-25526 (hubspot jinjava)...")
    headers = {
        "User-Agent": "CyberVault-Audit-Scanner/2.0",
        "Accept": "*/*"
    }
    try:
        r = requests.get(f"{target_url.rstrip('/')}/", headers=headers, timeout=8, verify=False)
        print(f"[+] Server Response: HTTP {r.status_code} | Server Banner: {r.headers.get('Server', 'Unknown')}")
        if r.status_code < 500:
            print(f"[!] Target reachable. Verify version against hubspot jinjava scope (*).")
        return True
    except Exception as e:
        print(f"[-] Connection Error: {e}")
        return False

if __name__ == '__main__':
    url = sys.argv[1] if len(sys.argv) > 1 else "http://localhost:8080"
    verify_vulnerability(url)
🛡️ Quick Patch & Remediation Script (Bash) patch_cve-2026-25526.sh
# Recommended Remediation & Patching Commands for CVE-2026-25526
# 1. Update package via distribution package manager:
sudo apt-get update && sudo apt-get --only-upgrade install jinjava 2>/dev/null || \
sudo dnf upgrade jinjava 2>/dev/null || \
sudo yum update jinjava

# 2. Inspect installed package versions for vulnerable scope:
dpkg -l | grep -i jinjava 2>/dev/null || rpm -qa | grep -i jinjava

# 3. Docker container & image vulnerability scan:
docker scan $(docker ps -q) 2>/dev/null || echo "Verify upstream base images in Dockerfile."

🛡️ Remediation & Security Action

  • Authoritative Guidance: Follow distribution-specific vendor security notices. Advisory status and package patches vary by distribution release.
  • Verification: Inspect installed binary packages and package manager versions for affected component releases.
  • Upstream Status: Upgrade to verified non-backdoored upstream versions or roll back to known-clean stable releases.
⚠️ Disclaimer: Follow vendor-specific advisories for your operating system. CyberVault does not fabricate unsupported remediation scripts.

❓ Frequently Asked Questions (FAQ) & Remediation Guide

How do I fix CVE-2026-25526 in hubspot jinjava?

Review vendor-specific security notices and update hubspot jinjava packages to the latest patched release immediately. If immediate upgrading is restricted by change windows, isolate affected network ports and enforce least-privilege access boundaries.

Is there an active exploit or public PoC for CVE-2026-25526?

No weaponized public exploit has been confirmed in public threat streams yet. Continuous surveillance is active across GitHub and security feeds.

What is the CVSS 3.1 severity rating and impact for CVE-2026-25526?

CVE-2026-25526 is classified with a CVSS 3.1 Base Score of 9.8 (CRITICAL). Check the metric breakdown above for attack vector requirements.

Risk Snapshot
9.8
CRITICAL SEVERITY
CVE ID CVE-2026-25526
Weakness CWE-1336
Vendor hubspot
Product jinjava
Published 2026-02-04
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H