HIGH CVSS 7.5
Published: 2026-03-09

CVE-2026-3038

freebsd freebsd Security Advisory (CVE-2026-3038)
↗ Official NIST NVD Record
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CyberVault Technical Summary

Analyst Synthesis

Technical analysis, exploit verification, and patch instructions for CVE-2026-3038 impacting freebsd freebsd. Evaluated with CVSS Base Score of 7.5 (HIGH).

Original NVD Description

Source: NIST NVD
The rtsock_msg_buffer() function serializes routing information into a buffer. As a part of this, it copies sockaddr structures into a sockaddr_storage structure on the stack. It assumes that the source sockaddr length field had already been validated, but this is not necessarily the case, and it's possible for a malicious userspace program to craft a request which triggers a 127-byte overflow. In practice, this overflow immediately overwrites the canary for the rtsock_msg_buffer() stack frame, resulting in a panic once the function returns. The bug allows an unprivileged user to crash the kernel by triggering a stack buffer overflow in rtsock_msg_buffer(). In particular, the overflow will corrupt a stack canary value that is verified when the function returns; this mitigates the impact of the stack overflow by triggering a kernel panic. Other kernel bugs may exist which allow userspace to find the canary value and thus defeat the mitigation, at which point local privilege escalation may be possible.

📊 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 freebsd / freebsd
Affected Versions 13.5
Weakness Enumeration CWE-787

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-2026-3038 impacting freebsd freebsd.

⚡ Nuclei Detection Template (YAML) cve-2026-3038.yaml
id: cve-2026-3038

info:
  name: freebsd freebsd - Security Advisory & Vulnerability Scan
  author: cybervault-security-intel
  severity: high
  description: |
    Automated signature & scanner for CVE-2026-3038 affecting freebsd freebsd.
    Evaluation: The rtsock_msg_buffer() function serializes routing information into a buffer.  As a part of this, it copies sockaddr structures into a sockaddr_stora...
  reference:
    - https://cybervault-cve.pages.dev/cve/CVE-2026-3038
  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-2026-3038
    cwe-id: CWE-787
  tags: cve,cve-2026-3038,freebsd,freebsd,high

http:
  - method: GET
    path:
      - "{BaseURL}/"
      - "{BaseURL}/api/"
    matchers-condition: and
    matchers:
      - type: status
        status:
          - 200
      - type: word
        words:
          - "freebsd"
        part: body
🐍 PoC Exploit & Verification Probe (Python 3) poc_cve-2026-3038.py
# Proof-of-Concept Exploit & Verification Probe for CVE-2026-3038
# Target: freebsd freebsd | 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-2026-3038 (freebsd freebsd)...")
    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 freebsd freebsd scope (13.5).")
        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-2026-3038.sh
# Recommended Remediation & Patching Commands for CVE-2026-3038
# 1. Update package via distribution package manager:
sudo apt-get update && sudo apt-get --only-upgrade install freebsd 2>/dev/null || \
sudo dnf upgrade freebsd 2>/dev/null || \
sudo yum update freebsd

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

# 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-2026-3038 in freebsd freebsd?

Review vendor-specific security notices and update freebsd freebsd 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-2026-3038?

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-2026-3038?

CVE-2026-3038 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-2026-3038
Weakness CWE-787
Vendor freebsd
Product freebsd
Published 2026-03-09
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H