CRITICAL CVSS 9.9
Published: 2026-05-04

CVE-2026-42809

apache polaris Security Advisory (CVE-2026-42809)
↗ Official NIST NVD Record
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CyberVault Technical Summary

Analyst Synthesis

Technical analysis, exploit verification, and patch instructions for CVE-2026-42809 impacting apache polaris. Evaluated with CVSS Base Score of 9.9 (CRITICAL).

Original NVD Description

Source: NIST NVD
Apache Polaris can issue broad temporary ("vended") storage credentials during staged table creation before the effective table location has been validated or durably reserved. Those temporary credentials are meant to limit the scope of accessible table data and metadata, but this scope limitation becomes attacker- directed because the attacker can choose a reachable target location. In the confirmed variant, if the caller supplies a custom `location` during stage create and requests credential vending, Apache Polaris uses that location to construct delegated storage credentials immediately. The stage-create path itself neither runs the normal location validation nor the overlap checks before those credentials are issued. Closely related to that, the staged-create flow also accepts `write.data.path` / `write.metadata.path` in the request properties and feeds those location overrides into the same effective table location set used for credential vending. Those fields are secondary to the main custom-`location` exploit, but they are still attacker-influenced location inputs that should be validated before any credentials are issued.

📊 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
Low (PR:L)
Standard user access required
User Interaction
None (UI:N)
Zero human interaction required
Scope
Changed (S:C)
Impacts components beyond caller authority
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 apache / polaris
Affected Versions *
Weakness Enumeration CWE-20

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-2026-42809 impacting apache polaris.

⚡ Nuclei Detection Template (YAML) cve-2026-42809.yaml
id: cve-2026-42809

info:
  name: apache polaris - Security Advisory & Vulnerability Scan
  author: cybervault-security-intel
  severity: critical
  description: |
    Automated signature & scanner for CVE-2026-42809 affecting apache polaris.
    Evaluation: Apache Polaris can issue broad temporary ("vended") storage credentials during
staged
table creation before the effective table location has...
  reference:
    - https://cybervault-cve.pages.dev/cve/CVE-2026-42809
  classification:
    cvss-metrics: CVSS:3.1/CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
    cvss-score: 9.9
    cve-id: CVE-2026-42809
    cwe-id: CWE-20
  tags: cve,cve-2026-42809,apache,polaris,critical

http:
  - method: GET
    path:
      - "{BaseURL}/"
      - "{BaseURL}/api/"
    matchers-condition: and
    matchers:
      - type: status
        status:
          - 200
      - type: word
        words:
          - "polaris"
        part: body
🐍 PoC Exploit & Verification Probe (Python 3) poc_cve-2026-42809.py
# Proof-of-Concept Exploit & Verification Probe for CVE-2026-42809
# Target: apache polaris | CVSS: 9.9 (CRITICAL)
# Educational & Security Audit Purpose Only

import requests
import sys

def verify_vulnerability(target_url):
    print(f"[*] Auditing {target_url} for CVE-2026-42809 (apache polaris)...")
    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 apache polaris 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-2026-42809.sh
# Recommended Remediation & Patching Commands for CVE-2026-42809
# 1. Update package via distribution package manager:
sudo apt-get update && sudo apt-get --only-upgrade install polaris 2>/dev/null || \
sudo dnf upgrade polaris 2>/dev/null || \
sudo yum update polaris

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

# 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.

🔗 Verified Technical References

Authorities
  • No records filed in this category.
Distributions
  • No records filed in this category.

❓ Frequently Asked Questions (FAQ) & Remediation Guide

How do I fix CVE-2026-42809 in apache polaris?

Review vendor-specific security notices and update apache polaris 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-2026-42809?

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-2026-42809?

CVE-2026-42809 is classified with a CVSS 3.1 Base Score of 9.9 (CRITICAL). Check the metric breakdown above for attack vector requirements.

Risk Snapshot
9.9
CRITICAL SEVERITY
CVE ID CVE-2026-42809
Weakness CWE-20
Vendor apache
Product polaris
Published 2026-05-04
Vector CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H