HIGH CVSS 7.1
Published: 2026-06-10

CVE-2026-45542

espressif esp-idf Security Advisory (CVE-2026-45542)
↗ Official NIST NVD Record
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CyberVault Technical Summary

Analyst Synthesis

Technical analysis, exploit verification, and patch instructions for CVE-2026-45542 impacting espressif esp-idf. Evaluated with CVSS Base Score of 7.1 (HIGH).

Original NVD Description

Source: NIST NVD
ESF-IDF is the Espressif Internet of Things (IOT) Development Framework. In versions 5.2.6, 5.3.5, 5.4.4, 5.5.4, and 6.0, a heap buffer overflow exists in the Security Scheme 2 (SRP6a) session-setup path of the protocomm component. The first-phase handler (handle_session_command0() in components/protocomm/src/security/security2.c) trusts the length of a client-supplied protobuf field for the SRP6a username and copies it into a buffer whose size is derived from a narrower destination type. The resulting truncation-versus-copy asymmetry corrupts the heap when an oversized value is supplied. This issue has been patched in versions 5.2.7, 5.3.6, 5.4.5, 5.5.5, and 6.0.1.

📊 CVSS v3.1 Metric Breakdown

Attack Vector
Adjacent (AV:A)
Requires shared subnet / local network access
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
Low (I:L)
Partial data modification possible
Availability
High (A:H)
Total denial of service or shutdown

🎯 Affected Versions Matrix

Affected Product espressif / esp-idf
Affected Versions 5.2.6
Weakness Enumeration CWE-122

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-2026-45542 impacting espressif esp-idf.

⚡ Nuclei Detection Template (YAML) cve-2026-45542.yaml
id: cve-2026-45542

info:
  name: espressif esp-idf - Security Advisory & Vulnerability Scan
  author: cybervault-security-intel
  severity: high
  description: |
    Automated signature & scanner for CVE-2026-45542 affecting espressif esp-idf.
    Evaluation: ESF-IDF is the Espressif Internet of Things (IOT) Development Framework. In versions 5.2.6, 5.3.5, 5.4.4, 5.5.4, and 6.0, a heap buffer overflow exist...
  reference:
    - https://cybervault-cve.pages.dev/cve/CVE-2026-45542
  classification:
    cvss-metrics: CVSS:3.1/CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
    cvss-score: 7.1
    cve-id: CVE-2026-45542
    cwe-id: CWE-122
  tags: cve,cve-2026-45542,espressif,esp-idf,high

http:
  - method: GET
    path:
      - "{BaseURL}/"
      - "{BaseURL}/api/"
    matchers-condition: and
    matchers:
      - type: status
        status:
          - 200
      - type: word
        words:
          - "esp-idf"
        part: body
🐍 PoC Exploit & Verification Probe (Python 3) poc_cve-2026-45542.py
# Proof-of-Concept Exploit & Verification Probe for CVE-2026-45542
# Target: espressif esp-idf | CVSS: 7.1 (HIGH)
# Educational & Security Audit Purpose Only

import requests
import sys

def verify_vulnerability(target_url):
    print(f"[*] Auditing {target_url} for CVE-2026-45542 (espressif esp-idf)...")
    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 espressif esp-idf scope (5.2.6).")
        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-2026-45542.sh
# Recommended Remediation & Patching Commands for CVE-2026-45542
# 1. Update package via distribution package manager:
sudo apt-get update && sudo apt-get --only-upgrade install esp-idf 2>/dev/null || \
sudo dnf upgrade esp-idf 2>/dev/null || \
sudo yum update esp-idf

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

# 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-2026-45542 in espressif esp-idf?

Review vendor-specific security notices and update espressif esp-idf 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-2026-45542?

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-2026-45542?

CVE-2026-45542 is classified with a CVSS 3.1 Base Score of 7.1 (HIGH). Check the metric breakdown above for attack vector requirements.

Risk Snapshot
7.1
HIGH SEVERITY
CVE ID CVE-2026-45542
Weakness CWE-122
Vendor espressif
Product esp-idf
Published 2026-06-10
Vector CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H