CVE-2026-76501 — A vulnerability in the Segment Routing over IPv6 (SRv6) Operation, Administration, and…¶

Key facts

CVE-2026-76501 is a Critical (9.8) vulnerability: A vulnerability in the Segment Routing over IPv6 (SRv6) Operation, Administration, and…. This entry ships a detection-only PoC and a Docker test lab.


CVE	CVE-2026-76501
Severity	Critical (9.8)
Detection / prevention	—
PoC	poc.py
Source	2026/CVE-2026-76501/

Details¶

English | 한국어

Description¶

A vulnerability in the Segment Routing over IPv6 (SRv6) Operation, Administration, and Maintenance (OAM) feature of Cisco NX-OS Software, known as NGOAM, could allow an unauthenticated, remote attacker to execute arbitrary code with root privileges or cause a denial of service (DoS) on an affected device.

This vulnerability is due to improper input validation of IP traffic when the NGOAM and SRv6 features are enabled. An attacker could exploit this vulnerability by sending crafted packets to an IP interface on an affected device. A successful exploit could allow the attacker to execute arbitrary code with root privileges and could cause process crashes resulting in a reload and DoS condition.

Vulnerability Details¶

Property	Value
CVE ID	CVE-2026-76501
CVSS Score	9.8

Proof of Concept¶

Download¶

# Download PoC script
curl -O https://raw.githubusercontent.com/fankh/vulnerability-poc/main/2026/CVE-2026-76501/poc.py

Usage¶

# Run PoC against target
python3 poc.py --target <TARGET_URL>

# With authentication
python3 poc.py --target <TARGET_URL> --username <USER> --password <PASS>

⚠️ Warning: This PoC is for authorized security testing only. It uses detection-only techniques and does not exploit or damage target systems.

Test Lab¶

This repository includes a Docker-based test environment with both vulnerable and patched applications.

Quick Start¶

# Clone and navigate to CVE directory
cd CVE-2026-76501

# Start both applications
docker-compose up -d

# Run tests
./run-tests.sh    # Linux/Mac
./run-tests.ps1   # Windows PowerShell

Application Endpoints¶

Application	URL	Status
Vulnerable App	http://localhost:8080	Shows vulnerability
Patched App	http://localhost:8081	Demonstrates fix

Directory Structure¶

├── README.md           # English documentation
├── README_KO.md        # Korean documentation
├── poc.py              # PoC detection script
├── docker-compose.yml  # Container orchestration
├── run-tests.sh        # Linux/Mac test runner
├── run-tests.ps1       # Windows test runner
├── vulnerable-app/     # Vulnerable version
│   ├── app.py
│   ├── Dockerfile
│   └── requirements.txt
└── patched-app/        # Fixed version
    ├── app.py
    ├── Dockerfile
    └── requirements.txt

References¶

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ngoam-rce-LWKQ4BU

Generated by PoC Generator on 2026-10-08T08:05:13.928385694

Frequently asked questions¶

What is CVE-2026-76501?¶

CVE-2026-76501 is a Critical (9.8) vulnerability: A vulnerability in the Segment Routing over IPv6 (SRv6) Operation, Administration, and…. This entry ships a detection-only PoC and a Docker test lab.

How do I detect CVE-2026-76501?¶

Run the detection-only PoC included with this entry against your Docker test lab to confirm whether a target is affected; pair it with your own IDS logging.

How do I block or mitigate CVE-2026-76501?¶

Upgrade to a fixed version per the vendor advisory; the NVD record lists the affected versions. Use the included PoC to verify your remediation.

For authorized security testing and research only. See the full source and NVD record.