HIGH CVSS 7.5
Published: 2026-05-05

CVE-2026-6322

openjsf fast-uri Security Advisory (CVE-2026-6322)
↗ Official NIST NVD Record
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CyberVault Technical Summary

Analyst Synthesis

Technical analysis, exploit verification, and patch instructions for CVE-2026-6322 impacting openjsf fast-uri. Evaluated with CVSS Base Score of 7.5 (HIGH).

Original NVD Description

Source: NIST NVD
fast-uri normalize() decoded percent-encoded authority delimiters inside the host component and then re-emitted them as raw delimiters during serialization. A host that combined an allowed domain, an encoded at-sign, and a different domain was re-emitted with the at-sign as a raw userinfo separator, changing the URI's authority to the second domain. Applications that normalize untrusted URLs before host allowlist checks, redirect validation, or outbound request routing can be steered to a different authority than the input appeared to specify. Versions <= 3.1.1 are affected. Update to 3.1.2 or later.

📊 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
None (C:N)
No data confidentiality impact
Integrity
High (I:H)
Total modification of target system
Availability
None (A:N)
No system availability impact

🎯 Affected Versions Matrix

Affected Product openjsf / fast-uri
Affected Versions *
Weakness Enumeration CWE-436

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-2026-6322 impacting openjsf fast-uri.

⚡ Nuclei Detection Template (YAML) cve-2026-6322.yaml
id: cve-2026-6322

info:
  name: openjsf fast-uri - Security Advisory & Vulnerability Scan
  author: cybervault-security-intel
  severity: high
  description: |
    Automated signature & scanner for CVE-2026-6322 affecting openjsf fast-uri.
    Evaluation: fast-uri normalize() decoded percent-encoded authority delimiters inside the host component and then re-emitted them as raw delimiters during serializ...
  reference:
    - https://cybervault-cve.pages.dev/cve/CVE-2026-6322
  classification:
    cvss-metrics: CVSS:3.1/CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
    cvss-score: 7.5
    cve-id: CVE-2026-6322
    cwe-id: CWE-436
  tags: cve,cve-2026-6322,openjsf,fast-uri,high

http:
  - method: GET
    path:
      - "{BaseURL}/"
      - "{BaseURL}/api/"
    matchers-condition: and
    matchers:
      - type: status
        status:
          - 200
      - type: word
        words:
          - "fast-uri"
        part: body
🐍 PoC Exploit & Verification Probe (Python 3) poc_cve-2026-6322.py
# Proof-of-Concept Exploit & Verification Probe for CVE-2026-6322
# Target: openjsf fast-uri | CVSS: 7.5 (HIGH)
# Educational & Security Audit Purpose Only

import requests
import sys

def verify_vulnerability(target_url):
    print(f"[*] Auditing {target_url} for CVE-2026-6322 (openjsf fast-uri)...")
    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 openjsf fast-uri 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-2026-6322.sh
# Recommended Remediation & Patching Commands for CVE-2026-6322
# 1. Update package via distribution package manager:
sudo apt-get update && sudo apt-get --only-upgrade install fast-uri 2>/dev/null || \
sudo dnf upgrade fast-uri 2>/dev/null || \
sudo yum update fast-uri

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

# 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-2026-6322 in openjsf fast-uri?

Review vendor-specific security notices and update openjsf fast-uri 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-2026-6322?

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-2026-6322?

CVE-2026-6322 is classified with a CVSS 3.1 Base Score of 7.5 (HIGH). Check the metric breakdown above for attack vector requirements.

Risk Snapshot
7.5
HIGH SEVERITY
CVE ID CVE-2026-6322
Weakness CWE-436
Vendor openjsf
Product fast-uri
Published 2026-05-05
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N