VirusTotal Scanner Cog added

Signed-off-by: Marc Ahlgrim <marc@onemarcfifty.com>
This commit is contained in:
Marc Ahlgrim
2022-10-03 12:23:25 +02:00
parent 4023e2d70e
commit c2ff226138
3 changed files with 204 additions and 0 deletions
+12
View File
@@ -188,6 +188,12 @@ class OMFBot(AutoShardedBot):
except Exception as e:
print(f"ERROR in setup_hook: {e}")
# transmit the VirusTotal Token to the scanner object
scanner = self.get_cog('Scanner')
if scanner is not None:
scanner.registervTotal(self.configData.getVToken())
print(f'TOKEN: {self.configData.getVToken()}')
# ######################################################
# send_random_message is called when the server is idle
@@ -384,6 +390,12 @@ class OMFBot(AutoShardedBot):
async def on_message(self, message : discord.Message ):
try:
x=message.author
except Exception as e:
# message has been deleted by the scanner
return
# ignore ephemeral messages
if message.flags.ephemeral:
return
+4
View File
@@ -43,6 +43,10 @@ class Config():
secretNode=self.getNode("secret")
return secretNode.get('BOT_TOKEN')
def getVToken(self):
secretNode=self.getNode("secret")
return secretNode.get('VTOTAL_TOKEN')
def getClientID(self):
secretNode=self.getNode("secret")
return secretNode.get('CLIENT_ID')
+188
View File
@@ -0,0 +1,188 @@
# #####################################
#
# a virustotal scanner cog
# listens for messages and scans URLs,
# domains and files
#
# #####################################
from asyncore import loop
import hashlib
from discord.ext import commands
import discord
import re
import vt
import asyncio
# #####################################
#
# some return values and constants
#
# #####################################
stFile=1
stURL=2
stDomain=3
rvHarmless="harmless"
rvSuspicious="suspicious"
rvMalicious="malicious"
rvUnknown="unknown"
# #####################################
#
# Class definition
#
# #####################################
class Scanner(commands.Cog):
vTotalAPIKEY=None
vtClient = None
# ############################################
# init routine
# ############################################
def __init__(self, bot):
self.bot = bot
genericDomainString='[-a-zA-Z0-9@:%._\\+~#=]{1,256}\\.[a-zA-Z0-9()]{1,6}\\b(?:[-a-zA-Z0-9()@:%_\\+.~#?&\\/=]*)'
self.domainRegExp=f'{genericDomainString}'
self.urlRegExp =f'(?:http|ftp|sftp)s?://{genericDomainString}'
# ############################################
# registervTotal creates the VirusTotal API
# ############################################
def registervTotal(self,vToken):
self.vTotalAPIKEY = vToken
# ##############################################################
# getVerdict submits domains, URLS and/or files to Virustotal
# for scan
# ##############################################################
async def getVerdict(self,vtObjectSring):
vtInfo:vt.Object
theVerdict=rvHarmless
try:
vtInfo=await self.vtClient.get_object_async(vtObjectSring)
except Exception as e:
theVerdict=rvUnknown
print(f"scanner vtInfo returned {e}")
if (not theVerdict == rvUnknown):
vtInfoAnalysis=vtInfo.get("last_analysis_stats")
print(f"scanner vtInfo returned {vtInfoAnalysis}")
m=vtInfoAnalysis["malicious"]
h=vtInfoAnalysis["harmless"]
s=vtInfoAnalysis["suspicious"]
if (s>h):
theVerdict = rvSuspicious
if (m>h):
theVerdict = rvMalicious
return theVerdict
# ##############################################################
# scan_message submits Attachments, URLs to getVerdict
# ##############################################################
async def scan_message(self,msg):
if msg.author.id == self.bot.user.id:
return
# if we have not yet used the client or if the
# client had been closed in between then we re-
# open it
if (self.vtClient is None):
try:
self.vtClient = vt.Client(self.vTotalAPIKEY)
except Exception as e:
print(f"Error in scan_message: {e}")
return
# check for domain names
checkEntries=re.findall(self.domainRegExp,msg.content.replace("\n",""),re.IGNORECASE)
if len(checkEntries) >0:
for c in checkEntries:
print("{} is a Domain".format(c))
# check for links
checkEntries=re.findall(self.urlRegExp,msg.content.replace("\n",""),re.IGNORECASE)
if len(checkEntries) >0:
for c in checkEntries:
newMessage="**SECURITY WARNING**\nAll URLs are scanned\n"
xmsg=await msg.reply(newMessage)
print("{} is a URL".format(c))
url_id = vt.url_id(c)
theVerdict = await self.getVerdict(f"/urls/{url_id}")
newMessage=f'{newMessage}\n>> Scan result: **{theVerdict}**\n'
await xmsg.edit(content=newMessage)
if (theVerdict==rvMalicious):
await xmsg.edit(content=f'**MESSAGE HAS BEEN REMOVED FOR SECURITY REASONS**\n')
await msg.delete()
# take further action
break
print("URL Scan finished")
if (not theVerdict==rvSuspicious):
await xmsg.delete()
# check embedded files
if len(msg.attachments) > 0:
newMessage="**SECURITY WARNING**\nFiles posted here are systematically scanned\nEven if the scan is negative the file may still be malicious\n"
xmsg=await msg.reply(newMessage)
for theAttachment in msg.attachments:
newMessage=f'{newMessage}\n>> hashing file {theAttachment.filename}'
await xmsg.edit(content=newMessage)
attachmentContent = await theAttachment.read()
sha256String = hashlib.sha256(attachmentContent).hexdigest();
newMessage=f'{newMessage}\n>> submitting hash to Scan Engine'
await xmsg.edit(content=newMessage)
theVerdict=await self.getVerdict(f'/files/{sha256String}')
newMessage=f'{newMessage}\n>> Scan result: **{theVerdict}**\n'
await xmsg.edit(content=newMessage)
if (theVerdict==rvMalicious):
await xmsg.edit(content=f'**FILE HAS BEEN REMOVED FOR SECURITY REASONS**\n')
await msg.delete()
# take further action
# #####################################
# hook into edited messages
# #####################################
@commands.Cog.listener()
async def on_raw_message_edit(self, rawdata: discord.RawMessageUpdateEvent):
channel = await self.bot.fetch_channel(rawdata.channel_id)
try:
msg = await channel.fetch_message(rawdata.message_id)
except Exception as e:
# message has been deleted by the scanner
return
if msg.author.id == self.bot.user.id:
return
asyncio.create_task(self.scan_message(msg))
#await self.scan_message(msg)
# #####################################
# hook into new messages
# #####################################
@commands.Cog.listener()
async def on_message(self, msg):
if msg.author.id == self.bot.user.id:
return
asyncio.create_task(self.scan_message(msg))
# #####################################
# The cog init
# #####################################
async def setup(bot):
await bot.add_cog(Scanner(bot))