HIGH CVSS 7.5
Published: 2026-02-23

CVE-2026-27623

lfprojects valkey Security Advisory (CVE-2026-27623)
↗ Official NIST NVD Record
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CyberVault Technical Summary

Analyst Synthesis

Technical analysis, exploit verification, and patch instructions for CVE-2026-27623 impacting lfprojects valkey. Evaluated with CVSS Base Score of 7.5 (HIGH).

Original NVD Description

Source: NIST NVD
Valkey is a distributed key-value database. Starting in version 9.0.0 and prior to version 9.0.3, a malicious actor with network access to Valkey can cause the system to abort by triggering an assertion. When processing incoming requests, the Valkey system does not properly reset the networking state after processing an empty request. A malicious actor can then send a request that the server incorrectly identifies as breaking server side invariants, which results in the server shutting down. Version 9.0.3 fixes the issue. As an additional mitigation, properly isolate Valkey deployments so that only trusted users have access.

📊 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
None (I:N)
No system modification impact
Availability
High (A:H)
Total denial of service or shutdown

🎯 Affected Versions Matrix

Affected Product lfprojects / valkey
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-2026-27623 impacting lfprojects valkey.

⚡ Nuclei Detection Template (YAML) cve-2026-27623.yaml
id: cve-2026-27623

info:
  name: lfprojects valkey - Security Advisory & Vulnerability Scan
  author: cybervault-security-intel
  severity: high
  description: |
    Automated signature & scanner for CVE-2026-27623 affecting lfprojects valkey.
    Evaluation: Valkey is a distributed key-value database. Starting in version 9.0.0 and prior to version 9.0.3, a malicious actor with network access to Valkey can ...
  reference:
    - https://cybervault-cve.pages.dev/cve/CVE-2026-27623
  classification:
    cvss-metrics: CVSS:3.1/CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
    cvss-score: 7.5
    cve-id: CVE-2026-27623
    cwe-id: CWE-20
  tags: cve,cve-2026-27623,lfprojects,valkey,high

http:
  - method: GET
    path:
      - "{BaseURL}/"
      - "{BaseURL}/api/"
    matchers-condition: and
    matchers:
      - type: status
        status:
          - 200
      - type: word
        words:
          - "valkey"
        part: body
🐍 PoC Exploit & Verification Probe (Python 3) poc_cve-2026-27623.py
# Proof-of-Concept Exploit & Verification Probe for CVE-2026-27623
# Target: lfprojects valkey | 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-2026-27623 (lfprojects valkey)...")
    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 lfprojects valkey 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-2026-27623.sh
# Recommended Remediation & Patching Commands for CVE-2026-27623
# 1. Update package via distribution package manager:
sudo apt-get update && sudo apt-get --only-upgrade install valkey 2>/dev/null || \
sudo dnf upgrade valkey 2>/dev/null || \
sudo yum update valkey

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

# 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-2026-27623 in lfprojects valkey?

Review vendor-specific security notices and update lfprojects valkey 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-2026-27623?

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-2026-27623?

CVE-2026-27623 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-2026-27623
Weakness CWE-20
Vendor lfprojects
Product valkey
Published 2026-02-23
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H