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I got a WhatsApp message from a number which is exactly mine but the last digit is increased by one (5 instead of 4). It was just a "Hi" and and a photo of a random guy. I asked who it is and he replied with something like "I'm the brother of your boss, he told me to message you". That's not true. After some days he se...
I have to use a USB stick that introduce itself as a HID device. I'm not sure if it does something fishy behind the scene or not, but I rather to think it's not safe and take the necessary steps to keep my system safe. My plan was to use it in a live Linux distribution; However, as mentioned here: How to prevent BadUSB...
I would like to provide some free tokens to users on registration, I don't want bot accounts to register and get free tokens. Is there any way to prevent this? I would like to use phone verification, but I am not sure if it's obsolete. I was able to find services that provide virtual numbers such as Twilio. So not sure...
As we already know, with the rising power of machines and new technologies like quantum computers today's methods of encryption might be much faster to crack in the future. With locally saved data you could always safely erase it and write it again with a stronger encryption method. However, I'm wondering what will hap...
Is it possible for someone to redirect text messages to you from another’s phone? Something weird is going on…over the last few weeks I have received “wrong number”text messages from people with similar motives. They start as “hey (some random name) this is (another random name) followed by a pic of “them” and when I t...
My google-foo failed me as most "how it works" sections related to fido are very... let's say... consumer-oriented. So openssh supports U2F natively when using the appropriate elliptic-curve-based cipher (namely ed25519-sk and the NIST one, do mind the -sk: it makes the whole difference). I could find no reference abo...
There is a room. There is a lot of incentive for people to enter this room. This room allows you to enter and exit whenever you want, but for each minute you stay in the room, you get a dollar. Problem is, it's very hard to get to the room and is located in the middle of nowhere, so not that many people want to go to t...
I am trying to privilege escalate a vulnerable box and I've stuck with this output: sudo -l Matching Defaults entries for charlie on sewers: env_reset, mail_badpass, secure_path=/usr/local/sbin\:/usr/local/bin\:/usr/sbin\:/usr/bin\:/sbin\:/bin User charlie may run the following commands on sewers: (roo...
My phone is encrypted and i was just playing with the configuration and just found a Trusted Credentials that got me curious on what it is and specially in one called Government Root Certification Authority (Government Root (CA) or Goverment(CA)) and i'm wondering what is that. Also i'm wondering what kind of vulnerabi...
If authorities find access logs or some other linking between an IP address and the access of illegal materials online, in order to trace down who the owner of the IP address is any IP assignment logs that links address to customer would have to still exist before an ISP deletes them. For example, if the logs they find...
it's been a while since WebRTC was seen as a possible opportunity for IP leak when using a VPN. We're in 2021 today and I was wondering if there have been some improvements with this protocol in term of security. I mean, Edge is currently WebRTC enabled by default, whereas Firefox is WebRTC disabled. So I tried a few w...
I am using CryptoJS AES 256 encryption: CryptoJS.AES.encrypt(realData, generateKey(passphrase), {iv: iv}); The secret is generated through: function generateKey(passphrase) { const salt = CryptoJS.lib.WordArray.random(128 / 8); const key256Bits = CryptoJS.PBKDF2(passphrase, salt, { keySize: 256 / 32, itera...
Is it conceptually possible to allow in the server a specific self signed client certificate for mutual TLS? If possible but not recommended. Why? I have a client to who I have to provide a server that does mutual TLS auth. But they say they wont sign our server certificate nor will they let us sign their client certif...
I added the client cert into ca.pem as in bind 0.0.0.0:443 ssl crt /etc/ssl/private/asdf.hdavid.io.pem verify optional ca-file /etc/ssl/certs/ca.pem http-request set-header X-SSL-Client-Verify %[ssl_c_verify] And then calling with curl -v --key key.pem --cert cert.pem https://asdf.hdavid.io But I get X-SSL-Clie...
I have two servers and frontend client: one server authorize and authenticate user, after that issue jwt token to client. Frontend client also visits second backend server using jwt token as Authorization Header. JWT secret is the same on the both servers(encrypted by SH256). Questions: Is there any alternative to k...
This 'mandatory' TPM thing worries me… if Windows 11 absolutely wants to use the TPM and takes ownership of it, and secure boot becomes mandatory how could we dual boot to i.e. Linux? Also, what about if the TPM is already in use (owned) by the other OS?
On Windows, user password hashes are not salted and, on Linux, user password hashes are stored in the same root-owned file as the salt. Given this, in what ways might a bruteforce attack to find the user's password using the known hash potentially be more efficient/faster/more successful than an similar bruteforce att...
I am making a series of python scripts for data overwriting. My current prototype creates a series of large files and simply fills the memory (using a different system for additional overwrites). Is there an advantage to overwriting the entire USB after removing all files rather than doing this in terms of protecting a...
Is it possible to "trick" a Windows 10 PC into thinking a flash drive is a mouse to execute code on the machine? If so, how? Note: I'm not trying to do anything malicious. All of this is strictly for learning purposes.
What's the required key usage/extended key usage for signing documents, eg.PDF, Word, PowerPoint, Excel, etc... I am going to create a self-signed certificate that is needed to sign those documents. I wonder which key usage is required as there are many types that I can choose. Note: I just need a self-signed certifica...
I recently was attacked by a ransomware that encrypted files in my computer and turning them into a .CRYSTAL file type. In the ransom note there is a “key id” which resembles a public key of sort, and a computer ID. I paid - and got a “key” and a decryption program. This decrypts 70% of my server but all the larger fil...
If you decrypt ciphertext to the terminal like this: gpg --output - --armor --encrypt --recipient 23642351 message.txt.pgp ..does it touch the hard drive / ssd or only live in RAM? What about when Thunderbird decrypts a message - does the plaintext touch the hard drive or only live in RAM? Thunderbird stores everythin...
I am currently trying to better understand this attack. If the network is open ie, not password, I would assume that it would be super easy for the evil twin to work. If I understand correctly, wireless clients won't be able to tell the difference both the legit and twin would look the same. Likely causing the evil twi...
I am new to memory forensics. When a process in Windows is ended are all artifacts for the process in memory gone? I ask because my EDR solution gives me the local process ID of a process I am trying to look at. I obtain a full memory and kernel image minutes later of the detection and I am unable to find the local ...
I bought a new router to isolate devices in my network, but then I found that famous Steve Gibdson's Three Dumb Routers episode. I have read the whole transcript but even so I didn't get why only two routers is not enough to isolate my local network. Three Dumb Routers suggests this: No trusted devices ...
So first, I know that VPN isn't exactly useful for anonymity. Did my homework about TOR and Tails. However, I still want to use VPN, NordVPN to be precise. I want to avoid causing a paper trail through PayPal payment, and they accept Monero. The Monero protocol itself seems to be pretty good. However, I also learnt th...
I recently heard about the Nym mixnet and am researching it and the Sphinx packet format. So far it looks promising, but there is one thing I'm unsure of. Networks like Tor use ephemeral keys to limit the length of time an adversary could compel each relay to reveal where it is routing the packets it receives to essent...
If the OS is responsible for ensuring that one process cannot access another process memory space, and the point of process isolation is to keep processes separate from one another, then how can a malicious process perform actions on another process, say for example a DLL injection? Example: In the Windows API how can ...
We have a site that have redirection path like so: http://www.example.com http://www.example.com/ https://www.example.com/ Notice how it goes from http to http first (added a /), then finally go to https While ideally it should first go to HTTPS before adding a slash, it is what it is now. Moreover, user final destin...
In my 13 years of Wordpress, I've never seen anything like this. About an hour ago I was alerted by one of my users that the website was displaying an Internal Server Error 500 message on every page. I consulted my host's tech support, and they were unable to determine the cause. I then noticed that I had about 20 comm...
I am currently trying to get an understanding of multi factor authentication. The biggest issue so far: When does "something you have" NOT get reduced to "something you know"? I want to have a "posession"-factor that does not get reduced to a "knowledge'-factor I don't think this is a question that can be answered easi...
I get false positive ports that are marked open when using nmap with proxychains-ng (Using a proxy list that contains socks5 proxies). I've tried a couple of techniques to debug this strange behavior (by following this tutorial False Positive TCP) but I could not find a proper explanation (note that I am a beginner at ...
If I understand correctly, a JSON Web Token (JWT) can be asymmetrically signed with a special private key (JWK). At least in some common configurations, the public part of the signing key can't be obtained via classic x.509 certificates, but rather by accessing some trusted API endpoint, fetching the public key, and us...
As per the question what are the risks? if we did go ahead with this and some of our users installed a supplier's VPN client on to our corporate machines, once the connection is establish can a threat actor from the supplier use that connection to jump on to our company network? The other risk i see is that there is a ...
If the website is legitimate and the attacker exploited that legitimate website, and the attacker gains access to a victim's system that visits the website, then it is a drive-by compromise. However, if the attacker built the website, and the attacker gains access to a victim's system that visits the website, will it b...
I am trying to secure access to a PHP page in a folder and only allow access to it from a specific IP Address and domain name but only on a specific port. I have seen a number of questions here but not including the PORT access. I have added the following in the .htaccess file within the folder. order allow,deny deny...
So I'm using an untrusted computer but on a trusted network (my home). The operating-system + hardware are trusted but the Profiles, certificates & software installed in the system are not trusted. I can in fact see a bunch of certificates installed on the machine by going into my Profiles settings with names such as "...
I want to understand if Openssl supports the key usage extension validation. If yes, how does it understand that each certificate in the chain received in server certificate correctly specifies the key usage ?
Last year Intel released a white paper on a joint research effort with Microsoft concerning the possibility to perform malware analysis by converting a file to an image and then applying a deep neural network model on it. In the said white paper the first stage in the process is defined as "Preprocessing", e.g. the con...
Summary We are running a web site (https only) and have a single bug report from a user that says the site gets warned as "Not secure". The user gets this warning only when accessing it from the Safari browser on an iPhone (iOS 14.6). Other users - also on iPhone/Safari - does not see the same message (just the padlock...
Sometimes there are websites I'd like to checkout but I have the feeling that the site may have something malicious in it, the easiest way would be to just load my VM and opening the site there, but thats a hassle sometimes, specially if I just want to do a quick check. Not saying that because of lazyness of having to ...
I'm doing a pretty bog-standard return-to-libc attack and I'm in a bit of a pickle. I first got the entire attack working with my local version of libc, then I used the version of libc provided by the challenge to work out the offsets on the remote target. It doesn't work on remote so I startup a Ubuntu Bionic containe...
I went through old threads on this forum and tried --resolve-all but it doesn't seem to work. If I use nmap -sn <hostname> It throws an error Failed to resolve <hostname> If I use nmap -sn --resolve-all <hostname> It still throws an error Failed to resolve <hostname> How to resolve this hostname and then perform nmap s...
Using Linux, is there anyway to detect that an arbitrary USB device is a BadUSB or not? For example: Booting a Linux into multi-user.target. No graphical interface / tty (getty login). Plug the USB into the PC. Wait and see if it starts typing any character on tty. Are these steps enough to detect a BadUSB? This ...
Let's say I have to leave my computer unattended and turned off for a while with some strangers, is it possible for someone to clone my HDD and SSD data?
This is the inverse of this question here. Google keeps prompting me to enable Two-Factor Authentication for my Google account. I don't like the inconvenience of TFA, such as mandating that I will always have my mobile device handy on me. Assuming that I have a secure (i.e. reasonably long and complex) password that is...
How much video uploading could be trackable for some person who uses the Tor Browser for uploading video on YouTube or other video hosting services with low authorization and sign-up processing, like Vimeo? And which group (hackers or …) have the ability to track this target?
If an SSD uses TRIM such as a Mac with TRIM support when it deletes files, I've been told that it is completely unrecoverable. Therefore, is it ever really better protection to physically destroy the SSD to protect one's data?
I would like to know if a website is fingerprinting me via WebGL, first of all, knowing if the site is doing it Knowing when they send the request to my browser Knowing what value I am reporting to the site Important thing to notice, in sites like https://webglreport.com/?v=2 How can I know where do I get the fingerp...
I tried reading few articles, however I'm not able to understand the merit of POP over Bearer token. Bearer token if lost (during transit over the wire) can give the holder of the token same privileges as the genuine owner. POP token is supposed to additional security by making sure that it has a component that is know...
Apologies if this isn't the right place to ask this. I occasionally get alerts from my Django website along these lines: Internal Server Error: /posts/specific-post/ UnboundLocalError at /posts/specific-post/ local variable 'comment_form' referenced before assignment HEAD requests are triggering these errors. This ...
I am pretty new in the security world and I am writing a procedure on how to create a memory image of an infected machine for forensics. The problem is that the machine does not have the tools for memory imaging before getting infecting. When infected, an incident responder must somehow install the tools to dump the me...
There is a web application that can upload HTML files and also download the uploaded file. When I upload an HTML file containing the script tag and download it, the response is as follows. HTTP/1.1 200 Date: Fri, 02 Jul 2021 01:11:11 GMT Content-Type: text/html Content-Length: 39 Connection: close Server: nginx/1.14.2 ...
I have a question relating to implementing encryption of data at rest. This is possibly more suited to another stackexchange site, so please let me know where would be better to post if I'm a little off base. My system has an NVME drive with OPAL 2.0 hardware encryption and a TPM 2.0 module. I am running Ubuntu 20.04 w...
I am studying spanning tree protocol attacks and I would like to understand a thing. The root is on the "top" of the tree, how can we exploit this to put in place an attack? We can, in some way, become the root, but what privileges would we get doing this? I don't get if the root can read all the packets, because I tho...
My company sends around 1M emails per month through various providers (Sendgrid etc.). One of emails we send is a "sign up" email, which contains a link for a user to finish registering their account. This morning around 5:21am we sent a batch of around 200 to a company in CA. Within a minute our system logged 200 erro...
I have seen dozens of client-side captcha verification on github and considering it is just a matter of time to make it totally useless, what are the purposes of these? Are there any justifications that I don't see? Maybe, the only thing I can think of is to only send the hash of the captcha to the client-side but I co...
When trying to go to https://www.pfizerpapconnect.com, the Firefox web browser claims there is a "Potential Security Risk" and pops up a page recommending to not proceed. Is there a real security issue with this site, and if so, what is it?
I use OpenWrt and by default all outgoing traffic is tunneled through Wireguard VPN endpoint (provider from the list of privacytools.io recommendations). Often I get an "Access Denied" or the page does not load (timeout). Famous local sites, which block legal VPNs (example Zalando). As a workaround I use the integrate...
Consider an electronic voting system with two goals: (1) ensure that the vote of each voter is correctly counted, and (2) ensure that no voter can create a proof of his/her/their vote. The reasoning for (1) is to ensure that the intent of majority is respected, and the reasoning for (2) is to curb the selling of votes....
I am planning to use a self hosted (Linux based) email server. However, the server will be on hosting providers machine. The hosting providers will have access to the physical machine. In that case, can they access the emails? If so, how can I protect my emails?
I am a beginner in hacking. I have been trying to hack Windows XP using the netapi exploit in metasploit, but every time, in the end, I get an error: Exploit failed [unreachable]: Rex::ConnectionRefused The connection was refused Exploit completed but no session was created. I even tried turning off the firewall and...
I read How secure are most FDE implementations? What are the disadvantage of only encrypting the HDD compared to FDE with secure boot. If I encrypt a disk in a running server, and someone gain access to the machine (because login to the machine was not hardened enough), can that person steal my data? Is asking for auth...
Regarding the newly discovered vulnerability PrintNightmare CVE-2021-34527 that has existed for years without being discovered, currently affecting almost all versions of Windows, server and workstation alike, and for which there is no patch as of the time of this writing July 3rd 2021, the best recommendation currentl...
I've read other some articles (including this: https://medium.com/@technospace/tls-handshake-under-the-hood-79d20c0020de) and similar questions but none exactly like this hypothetical scenario. What if there is a "man in the middle" between the client and the certification authority and the same MITM is also between Cl...
I set up Thunderbird to use PGP a while ago, so I can sign and decrypt messages now. But I have forgotten my private passphrase for my private key, but since Thunderbird can do it anyway, it has it stored somewhere. How can I get it? I already know that the password, with which encrypted-openpgp-passphrase.txt – the ...
Assuming I use AWS to host a service with quite sensitive personal data, is it possible to hide traffic and stored data from amazon? I would assume the answer is no. I think I need to provide all the keys, especially the private SSL-key, to amazon so that the service can run in the first place. This means that amazon c...
I generally wanted to know how a certificate works, I mean a certificate distributed by the Certificate Authority to identify the identity of a sender. How does it work? Can you use simple and easily understandable words? Thank you
I read this blog (cached version) (and the related cached tweet) about replacing TCP/IP with blockchain. Tweet: The Internet has a serious fundamental flaw: the transmission control protocol/internet protocol (TCP/IP)—the primary engine underpinning the Internet—is less secure. Is #blockchain the solution we need to e...
I believe it is fairly common knowledge that there are security and privacy concerns regards WhatsApp. The EFF, Ed Snowden, and many others, have expressed concern about the apps' integrity. You don't need to be a conspiracy nut or a guy with a tinfoil hat, in order to enjoy basic privacy. I have been trying to delete ...
When using Google SSO, does this count as only one factor of authentication or as many factors as I use for my google account? If it counts as a single factor, would this be "something I have" in the sense that I have access to this account?
I'm digging into UUIDv1 generation and bruteforce, in order to take control of a password reset feature of a website which sends a link with a get parameter token=UUIDvX. I'm trying to identify which version of UUID hashing algorithm the server uses. Being able to generate the right UUID would lead to any registered ac...
I work in gov organization and recently I learned they set up a MITM, by installing some certificates - so when I visit any web site and then check the certificate info it shows the certificate installed by my organization. My question is, will using Tor, protect me in such scenario, e.g. if I visit Facebook, will my p...
Question is for transfer encrypted data between two services (Like HTTP, GRPC or etc...) Can I transfer IV and AuthTag in plain, Is this approach secure? I have sample code in Node.js and I'm not crypto expert. See the code for more info: const crypto = require('crypto'); class AES { static encrypt(string, key) { ...
I'm trying to simulate a race condition in Go to replicate a time-of-check time-of-use vulnerability (https://en.wikipedia.org/wiki/Time-of-check_to_time-of-use). The code below takes in a user-provided fruit and searches for it in an array. If the fruit is found it returns the name of the fruit: package main func che...
According to this Dr. Web article: Doctor Web’s malware analysts have discovered malicious apps on Google Play that steal Facebook users’ logins and passwords. These stealer trojans were spread as harmless software and were installed more than 5,856,010 times... The applications were fully functional, which was suppos...
Can I secure a website using a simple whitelist system? My idea is to port forward a website www.example.com on my pc. To secure it, I want to add a whitelist system. It will work like this: When the server receives a request, it will read a file containing a list of allowed IPs and check if it contains the requester's...
I've noticed a lot of weird logs in /var/log on my server. For example: cd /var/log/DIST00000001ARGC00000005ARGV00000002ccARGV00000002-cARGV00000006nmap.cARGV00000002-oARGV00000006nmap.oDOTI00000000 sudo cat user.log Jun 30 16:48:08 DIST00000001ARGC00000005ARGV00000002ccARGV00000002-cARGV00000006nmap.cARGV00000002-oAR...
I have been using cryptsetup for a while now and just found out about the option 'luksDump'. I am used to similar tools like veracrypt and truecrypt and I am a bit shocked that all these vulnerable data are so easily accessible. If I remember it right, vera- and truecrypt made it impossible to find out cipher and hash ...
I was reading this article about session tokens from Mozilla's Developer website. Historically, I've always assumed that a session token set with a blank expiry (or one set to zero) would expire at the end of a session. This seems to be backed up by John Wu's answer here: https://security.stackexchange.com/a/47419/7853...
These tools work based on "hashes", but they seem to not mean that in traditional sense, since they can also extract hashes from a variety of formats like kdbx and zip. I doubt all these formats also keep a hash of the password inside themselves that the tool extracts and then tries to crack. So like what does hash mea...
Here is my exploit: junk = b'A' * 1032 ​ eip = b"\xf5\x93\x4a\x00" # some address where 'jmp esp' lives shellcode = b"" shellcode += b"\x33\xc0" # xor eax, eax shellcode += b"\x50" # push eax shellcode += b"\x68\x2E\x65\x78\x65" # push ".exe" shellcode += b"\x68\x63\x61\x6C\x63" # push "cal...
I have an embedded device running Armbian which I was able to get the drive image from. The entry in /etc/shadow combined with /etc/passwd after unshadowing is this: root:$6$TV6ML2bG$TncnN/adtU9xaQs/OpmkWzpMIGuYexLf.timEI28P5RIPn5xjKRu.aibfgss2OdXoyXK.Dhh3yQPAsRHQLx.1/:0:0:root:/root:/bin/bash I am just learning JtR n...
I did some research about how secure and private SMS messages are. Providers and governments can see these SMS messages in plaintext, but what is weird is that these messages are not encrypted in transit. According to my knowledge, that makes the service vulnerable to MiTM attacks: a semi-skilled hacker who knows my lo...
Why service providers didn't implement something like SSL to make SMS more secure and reliable in multiple scenarios ? I did ask a question about why SMS is used as a way of verification while it is not encrypted in transit.
During an engagement, I found a potential XSS vulnerability on a page. There is an HTML form that is submitted to this page (POST method) and sent parameters are reflected (without encoding) in the response. If I use a proxy tool (e.g. Burp Suite) and change my request POST body from: param1=val1&param2=val2&param3=val...
We have cloud based digital platform at work and we have the ability to connect to our cloud based ERP system. The ERP provider has given 2 options to connect - 1) a connector which uses HTTPS or VPN. I am trying to make a decision as to which is the most secure and easy to implement. Both TLS connection and VPN provid...
When you log into a website, it stores cookies that let your browser access the website without having the password. Given that some sites support yubikey for login, does it mean that the yubikey actively signs requests from my computer, or it just does a login and stores cookies? In the first option, it would be bette...
Why is it necessary to store operating system passwords hashed? From what I've learned, passwords are stored on the hard drive/SSD in /etc/shadow. However, if a malicious agent was able to get access to this file, doesn't that mean they can potentially access all the user's other files? If so, what is the point of crac...
No idea where to begin, I would like to ask for tips, direction and approaches when it comes to performing such a web testing. Source code analysis is not within scope for this test. I intend to run scanning tools (nmap, nikto, etc) on the website's server.
Assume I have a password manager that stores the credentials for a login to a 3rd party service. In this credentials the username, password and a TOTP-seed is stored and the current TOTP-token is displayed at all times and refreshed accordingly (Note that such a password manager does not exist). Is authenticating to th...
I work a lot with OWASP Zap, and I am very satisfied. Nevertheless, I have the problem with all my scans that I always have false positives in the PiiScan area. Among other things, Googlemaps numbers, or product numbers are recognized as Visa card numbers. I have not seen any way to prevent this, but I am looking for a...
As a developer, I ask how to approach security concerns regarding permissions of a binary which needs access to resources only available to root users. For example, let's think of a simple tool which creates a virtual device or executes commands which may not be executed by the user opening that application. The easies...
I understand that servers might want to prevent bad origins somehow stealing certain data and crafting a request to request some authorized data from a different domain. Such as using "Authorization" header etc., what is the use of Access-Control-Allow-Headers for unauthenticated endpoints? In such cases, shouldn't ser...
I recently came across this viral post on Facebook: As of the time of this question, the post has more than 37,000 likes, 33,000 shares and 1.5k comments. Most of the comments are positive, interspersed by the occasional techie questioning why someone would need such a powerful PC to request nudes to be taken down fr...
If your microservice architecture responds with error codes revealing which microservice had an error, doesn’t this reveal to the caller information on how your microservice architecture is designed? Caller -> Service A -> Service B -> Service B error Error codes: ServiceA-000001 ServiceB-000001 ServiceC-000001 So if ...
My question is how to detect ADB connection or unusual user activity in shell on the Android devices. I have an Android 5.1.1 device with Wi-Fi hotspot enabled and also with opened ADB port, similar to the setup in this challenge, except that I do not have a web server running on it, just ADB is directly open. Now I wa...
I'm trying to run a module against several IPs. It happens that usually we can use RHOSTS file:/file.txt but in this case, that option is not available. I have tried this https://www.pentestpartners.com/security-blog/scripting-metasploit-to-exploit-a-group-of-hosts-a-how-to/ My iter_rc.rc file is like this <ruby> host...
In the AH mode for IPsec, we include the IP header to ensure data origin authentication, and in the ESP, we exclude the IP header. what are the security properties we lose by not authenticating the IP address in the ESP mode? What security properties will we lose if we exclude port number authentication from ESP mode?...
I am developing a web application that is integrating with a third-party that does not have OAuth capability, but instead use a variety of account IDs and keys to generate tokens for API calls. On the Front End, we have created a text field to paste the account key file content that is generated by the customer on thei...