HIGH CVSS 7.5
Published: 2026-03-02

CVE-2026-3338

amazon aws-lc-sys Security Advisory (CVE-2026-3338)
↗ Official NIST NVD Record
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CyberVault Technical Summary

Analyst Synthesis

Technical analysis, exploit verification, and patch instructions for CVE-2026-3338 impacting amazon aws-lc-sys. Evaluated with CVSS Base Score of 7.5 (HIGH).

Original NVD Description

Source: NIST NVD
Improper signature validation in PKCS7_verify() in AWS-LC allows an unauthenticated user to bypass signature verification when processing PKCS7 objects with Authenticated Attributes. Customers of AWS services do not need to take action. Applications using AWS-LC should upgrade to AWS-LC version 1.69.0.

📊 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 amazon / aws-lc-sys
Affected Versions *
Weakness Enumeration CWE-347

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-2026-3338 impacting amazon aws-lc-sys.

⚡ Nuclei Detection Template (YAML) cve-2026-3338.yaml
id: cve-2026-3338

info:
  name: amazon aws-lc-sys - Security Advisory & Vulnerability Scan
  author: cybervault-security-intel
  severity: high
  description: |
    Automated signature & scanner for CVE-2026-3338 affecting amazon aws-lc-sys.
    Evaluation: Improper signature validation in PKCS7_verify() in AWS-LC allows an unauthenticated user to bypass signature verification when processing PKCS7 object...
  reference:
    - https://cybervault-cve.pages.dev/cve/CVE-2026-3338
  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-2026-3338
    cwe-id: CWE-347
  tags: cve,cve-2026-3338,amazon,aws-lc-sys,high

http:
  - method: GET
    path:
      - "{BaseURL}/"
      - "{BaseURL}/api/"
    matchers-condition: and
    matchers:
      - type: status
        status:
          - 200
      - type: word
        words:
          - "aws-lc-sys"
        part: body
🐍 PoC Exploit & Verification Probe (Python 3) poc_cve-2026-3338.py
# Proof-of-Concept Exploit & Verification Probe for CVE-2026-3338
# Target: amazon aws-lc-sys | 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-2026-3338 (amazon aws-lc-sys)...")
    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 amazon aws-lc-sys 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-2026-3338.sh
# Recommended Remediation & Patching Commands for CVE-2026-3338
# 1. Update package via distribution package manager:
sudo apt-get update && sudo apt-get --only-upgrade install aws-lc-sys 2>/dev/null || \
sudo dnf upgrade aws-lc-sys 2>/dev/null || \
sudo yum update aws-lc-sys

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

# 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-2026-3338 in amazon aws-lc-sys?

Review vendor-specific security notices and update amazon aws-lc-sys 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-2026-3338?

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-2026-3338?

CVE-2026-3338 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-2026-3338
Weakness CWE-347
Vendor amazon
Product aws-lc-sys
Published 2026-03-02
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N