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A while ago my PC kind of got frozen. The mouse was moving but I couldn't open other windows and I couldn't open the task manager pressing ctrl-shift-Esc. After a couple of minutes I just pressed the power button and forced it to restart. Before entering my laptop's password I got a message that because of failed log-i...
My DSL-WiFI router provides MAC address filtering. This is used for access restrictions, e.g for parental controls to keep certain devices off-line during certain hours. A device on the restriction list remains associated with the WiFi AP (router), but access to the internet is prevented by the router. HOWEVER, when a ...
Let's say I have aggregated ~1GB of data in memory into a string or corresponding data structure. My goal is to encrypt this data before sending it over the wire. With my limited understanding of encryption, I was looking into asymmetric key encryption and using a public key to do this task. Upon a couple Google search...
Assume the following very basic hashing algorithm. h(k) = k mod 17 Let's say we create a password 12345 for a website that uses this very basic hashing algorithm. That would yield the hash of 3. Say a brute force attacker comes by and starts guessing numbers starting at 1 they would only have to get to 3 before they g...
I have recently launched a new django based api, and quite quickly, I started to receive INVALID_HOST_HEADER SOME RANDOM URL errors. My understanding is that this is caused by somebody manually changing the HOST header, or proxying my API through some other domain. This is probably a basic question, but what is the poi...
I read that mobile network providers can block IMEI numbers from most networks but I also read that criminals can change these IMEI numbers in order to regain access to a network. How is this done and what can I do to protect myself from it?
Am investigating a macOS Catalina machine that is believed to be infected with malware. Have been viewing packets with tcpdump and noticed, on connecting to any web address, there are legit packet that gets sent to the DNS server... then... there are packets that get sent from 127.0.0.1:53482 (or some port) to 127.0.0....
I'm having a friendly debate with a co-worker as to the meaning of "self-signed" when it comes to PKI. We have an internal root and subordinate CA in our organization. We import the cert chain on internal clients to allow for the trust of certificates issued from our internal/private CA. My colleague believes that th...
I run an airflow instance which python process scheduler, which is used to trigger different python ML process which has no relation to crypto mining. This is the process which is running this dockerized process https://github.com/puckel/docker-airflow I still have no idea if it's a false positive from google's side or...
My DSL/WiFi router lists the IPv6 GU- and LL- Address for each connected device, alongside the device's MAC address. When a device uses VPN, these addresses disappear from the LAN status listing. Why is that? Is the VPN dropping to IPv4? I am asking this, because the VPN circumvents the parental controls of the router...
I was surprised to notice that sending email from a local server account allows any user to send a message with: From: whatever@whateverdomain This is a security issue, because it allows identity spoofing. When sending email from a local server account, email are put into the maildrop directory and Postfix daemon pic...
Kerberos is an authentication protocol that is famously built using only symmetric ciphers. As a direct result of this, there are several attacks possible, such as AS-REP Roasting AS-REQ Roasting Kerberoasting Silver Tickets Golden Tickets While some attacks require specific conditions (e.g. AS-REP Roasting requires ...
I want to do a formal cost-benefit analysis of security measures - and hence am looking for hard statistics about the probability / frequency of desktop machines being compromised (not recommendations of how to avoid this). I appreciate that this will vary massively depending on how well managed a particular estate is,...
I understand the need to use a VPN when connecting to public wifi. I also understand the need for a VPN when connecting to the company's internal network. However, I am less certain about the benefits of using a third-party VPN (NortonVPN in this case) when working from my home network. My employer is under the impress...
I am legally obliged to distribute a document (probably by email, probably saved as MS word, or a PDF) to several hundred recipients. The recipients are legally obliged to keep it confidential. However, based on past experience I'm pretty sure it's going to end up publicly leaked pretty quickly. (in the past it's been ...
I had a question about Tor and the anonymity status of a fully decrypted packet that leaves a Tor exit node. My high-level understanding is that prior to a packet traversing the Tor network, a Tor client chooses 3 Tor relay nodes for the packet to go through and encrypts a packet with the exit node's public key, then ...
I'm trying to change the value of a cookie using the Burp option, "Match and Replace". Here is my configuration: Item: Request header Match: cookieName:.*; Replace: cookieName:myValue; Type: Literal. Unfortunately, it does not work with this configuration. Do you have any suggestions?
I'm considering how to deploy a service that needs SSH access to many important boxes in my infrastructure. Rather than store a long-lived SSH private key in a key store that the service could request, I'm considering using short-lived SSH certificates to allow SSH access for the service. So the two architectures I'm c...
I'm talking about Online activation. My current workflow is: User pays via paypal (without registration) Paypal performs a request to my API. My API returns a serial key to the user. Then the user is able to register using this serial key. Is a "pay to register then use" and not a "register then pay to use". So the ...
I understand the necessity of using VPN when connecting to the work network from the outside. What I want to know is there any benefit for a strictly consumer computer that is connected to the internet but only for non-work things? Does it protect against viruses or people taking over your computer for example?
I was inspecting LDAP packets wit Wireshark today. When I authenticate with simple bind, I can see the password in plain text and subsequent LDAP requests and responses. Then I was authenticating with SASL/DIGEST-MD5. I can see the authentication attempts in clear text, except for the hashed credentials. But all subseq...
I know the methods for running possible malicious programs safely but how do I keep my computer secure when I need to use a tool that might be malware. I cannot run it in a sandbox or virtual machine since it requires access to hardware level control.
Now don't get me wrong, there are already other questions like this. But I'm looking into more of how an attack could actually be done. Instance A: A hacker gains access to a web server / hosting. They make changes to files so that instead of the original code, malicious code will run. Ok, so I think scenario has many...
I'm trying to protect my code from XSS. I used a tool to identify risks and it alerted the following code part as a possible injection case. var urlParams = new URLSearchParams(window.location.search); var param = urlParams.get('param'); var newUrl = "/" + param + "/goto"; document.write("<a href="+newUrl+">Link</a>");...
Let’s consider this scenario: An attacker got a valid certificate for a HSTS protected domain https://example.com. Can he still perform a man-in-the middle attack even if the website is already loaded in the browser HSTS list? I remember using Burp suíte once and getting a strict transport security related error for a ...
Scenario is as follows: In a vulnhub lab, I got limited shell. By means of attacker> nc -lvp 1234 victim> nc _attacker_ip 1234 I found out that ubuntu's ufw is limiting outgoing traffic. Since I'm no root, I can't list ufw rules. Is there any software that can detect outgoing rules? I guess it wouldn't be that hard to ...
I recently read about request smuggling. This is a very interesting attack that I didn't know about. A vulnerability to this was recently discovered at Slack, disclosed responsibly and a bounty was awarded. The linked article says: When the front-end server forwards HTTP requests to a back-end server, it typically s...
I'm wondering if the following code is vulnerable to command injection in bash: sumo /bin/netflash -Uk $CONTROLED_OPTION 2>&1 I'm thinking since it's not included in " " it should be vulnerable but I'm not sure since I can't make the command injection work, I tried $() `` | && ||  but nothing is working. or do I nee...
I am trying to make a restriction to procfs like only a certain groups of members can perform read and write actions. kernel document says we can do that by setting hidepid and gid in /etc/fstab. It will restrict the malicious user from making read and write on procfs but I have a doubt whether it is possible for malic...
I am learning about microservice security and I wanted to see if Netflix really logs me out. While logged into Netflix, I opened https://www.netflix.com/YourAccount and in inspector viewed headers I am sending. After copying the headers, I logged out -> opened Postman and issued the same request with the copied headers...
Facebook Apptoken uses OAuth2 client credential code. But the client_id and client_secret are sent to the servier via HTTP GET method. Isn't this unsecure ? For instance, any node that has logging enabled between the client and the Facebook server will log the GET URL. Thus exposing login credentials in their logs in c...
Please hear me out. I used to scoff at people who asked this question because client-side hashing is "so obviously wrong." I have read similar questions on this site but haven't found a satisfactory answer. Why hash on the server instead of the client? If the goal is to prevent someone with access to the password datab...
I was experimenting to see if I can make an ROP chain within the kernel. In the kernel debugging mode, I can make the first jump to an arbitrary gadget address without any problem. But the problem occurs after that. If I want to continue the kernel by typing continue, Kernel freeze. OS did not respond, I have to restar...
If I have a profile photo associated with a Google account, then when I enter my email address into GMail, but before I enter my password, the photo is shown. Is there a possible security breach there? For instance, if someone guesses at an email address, perhaps after obtaining part of it, the photo appearing confirms...
I'm investigating a login system that exposes (probably) hashed passwords. Password: HTSr0MF8Ou4liOCUayXHDg== The password is stored in base64 format. When I decode it, I get random 8 chars regardless of password length. The characters consist of random unicode characters. So, I know it's not an algo that I know like ...
I have Kali Linux installed on my computer, I have VMware Workstation 15.5 downloaded on my Kali machine, and I have also vulnerable VMs on VMWare but I don't know how to get IP of vulnerable VMs like necromancer, Kioptrix, etc.
If I were to design an end-to-end encrypted chat solution my initial naive solution would just use diffie hellman symmetric key exchange, or RSA public private keys, then encrypt the messages between the two users. Being a traditional REST API developer, I would use some sort of REST API to pass the keys between the t...
Lately I have been receiving messages from accounts on Discord telling me that I have won 1 BTC in a giveaway. This is obviously not true, but I have a hard time seeing how these accounts will get anything useful out of me falling for this. The instructions in the message for getting the 1 BTC goes like this (with a lo...
I found a website where I can upload any file I want. Now what are the biggest threats for them if they didn't install PHP (so a php shell can be uploaded, but it won't execute)? I found no sign of ASP either.
Situation I was about to install Skype on a laptop driven by Ubuntu 18.04 LTS Desktop. The software installation helper graciously informs me that Skype is unconfined. It can access all your personal files and system resources as per the screenshot below. Apparently there must be reasons to make a distinction from a...
Are there any character encoding mixup attacks that are still a threat in 2020? Such as with XSS or SQL injection being the most obvious. Some examples: Tricking a browser to display a page in UTF-7 despite XSS filtering was done in UTF-8. +ADw-script+AD4- processed as UTF-8 with htmlspecialchars() in PHP would go t...
Let's say there is a website called Service. Service has a read-only API. A user of Service has an API key that they can change at any time if they think their API key has been compromised. If I want to read info on a user from the API, I just give Service a url like service.com/api&request=info1,info2&key=aBc123 and I...
I run a few WordPress instances. I had one new one that I had not configured and left sitting, so the installation was on the 1st step awaiting for the database name, username, password, and host. When I went to finish the install after letting it sit like that for a week, I had noticed that someone had found the site,...
How can I determine the exact start byte and exact end byte of a LUKS header on a block storage device? I use Linux Unified Key Setup (LUKS) for Full Disk Encryption (FDE), so all of the data on my drive is encrypted using a strong master key that's not derived from my passpharse, and I'm working on a script that will ...
In analyzing the LUKS header on an encrypted volume, the cipher-name field shows a single-character = '@'. What does that mean? The LUKS On-Disk Format Specification originally published by Clemens Fruhwirth in 2005 clearly defines the encoding of the LUKS header, which states that the first three data fields are as fo...
Why is the metadata in my LUKS header listed twice? I started poking at the bits in a drive that's encrypted with LUKS, and I found some metadata in a JSON object. What's odd though is that the same JSON object actually appears twice. Here's a snippet of a hexdump that shows what I mean root@disp85:~# hexdump -Cn 99999...
Apparently having 100% prevention of SQL Injection and XSS attacks is easier said than done, but why? Can't static code analysis tools ensure that all user supplied input vectors (including user tainted variables) are sanitized? Or enforcing it with a restrictive programming language or framework? Wouldn't the below ...
I have a simple static webpage that lets users sign-up for a newsletter. Once they enter their email address, it gets sent to a public endpoint (AWS Lambda). This lambda function forwards the email address to a subscription list manager endpoint (Mailchimp) along with the API key. The connection between the AWS Lambda ...
So, to clarify, I'm currently working on a CTF challenge that consists of running an strace over on a bash script that is running vim commands using commands like vim -c ":!cat flag.txt" inside of a bash script. For some clarity, this idea was heavily inspired by a CTF I did recently and here's a writeup of what it loo...
Is it possible to store the master decryption key for accessing a LUKS encrypted volume inside an SGX enclave so that the master key cannot be accessed by any user on the system, even the root user with privileges to make system calls? Currently, LUKS necessarily has to store the master key in memory that's used to dec...
In my application I want a page to be accessible to the user only after s/he has entered the password again to prevent someone else opening that page in case the user has left a logged-in device open. The application uses JWT tokens for authentication. How should I implement a re-verification of the password and preser...
I found some serious vulnerabilities in my university's infrastructure. The infrastructure is a web app built with Spring and it's developed and used solely by the University. Using it I can get sensitive information for all students and gain access to their accounts on the infrastructure. I'm planning to coordinate a ...
My question is not about the recovery of deleted file, nor is it about the complete wiping of a disk; it's to ask about the traces deleted files leave, and how I could possibly 'see' them or visualise them? I'm very much interested in the right to be forgotten, data loss, technological decay etc. Which made me question...
What type of risks do I expose myself to by enabling flash in the browser? Web developers or online game developers who can use those vulnerabilities to crash my computer or exploit it by downloading files into my computer without permission? Or by making the browser more exploitable to hackers who use the same public ...
I have several external (client owned) servers communicating with an EC2 instance using a program installed on their servers (by me). Currently the program performs no authentication, We install the program on client servers, then add their IP to an AWS security group attached to our EC2 instance. We are currently run...
I was trying Invoke-ReflectivePEInjection by doing .\Convert-BinaryToString Convert-BinaryToString C:\file.exe $InputString="base64string" $PEBytes=[System.Convert]::FromBase64String($InputString) But when I run Invoke-ReflectivePEInjection -PEBytes $PEBytes I get Invoke-ReflectivePEInjection : The term 'Invoke-Refl...
Currently, my webserver support TLS 1.0 TLS 1.1 TLS 1.2 One of your single sign-on clients will move to TLS 1.2 on 1st April 2020. Can I remove TLS 1.0 and TLS 1.1 now? Or I need to wait till this client move to TLS 1.2, then only we can remove it. What will be the advantage for us to remove TLS 1.0 and TLS 1.1...
I'm building a website that gives awards to users. After each game I ask the user for their email and send them an email to claim their gift. Is there anyway to make sure that one user isn't simply opening new emails to take all the awards ? IPs can be changed so restricting them isn't a solution.
I am a developer and I have been looking more into security / pen-testing to make sure my application is secure. A lot of the resources I have looked at mention having a "pen-testing machine/lab/box," which sounds to me like people are using a completely isolated machine for their testing. However I am wondering if i...
I am learning about web security, but I'm very confused about URL Encoding. On PortSwigger, I learned that the URL http://127.0.0.1/admin can be written as http://127.0.0.1/%2561dmin by encoding a as %61 and then encoding % again, thus making it %2561 When I try this on my local computer, single URL encoding works. ht...
I shall begin my question with the remark that I am not tech savvy at all! The problem is the following: A cluster of computers (laptops, desktops, etc.) A, B, C, D... are all connected to the same router. Let's say my computer is computer A and I am a guest at big brother Bob's home, who owns the router and computers ...
What is the point of geoblocking IP addresses with cisco firepower or a similar service if the firewall would block the request anyway? For example, We only do business in the USA but see source IP's from Russia/Netherlands etc hitting the firewall all the time. Sometimes the IP's are part of a botnet/wannacry affili...
I do not have a lot of experience in networking, however, I have built a live-chat application using socket.io and nodeJS. In order to do this, I had to open a port to allow other networks to connect. How can I ensure that the open port does not leave vulnerabilities? Also since the client is connecting to my public I...
As part of their day-to-day work, each member of our analysis team must handle a variety of sensitive information. For example: username and passwords for our internal databases, and tokens for accessing APIs. Some of this is specific to each individual, while some are shared by the whole team. Ideally, each team membe...
My server software is using TLS with self-signed ED25519 (for small size) certificate. My client software is accessing said server. Considering I don't care about DNS/IP names, is it secure to disable standard TLS verification and compare peer public key against pre-shared in config? In pseudo-code: tls_connect/listen(...
I have just launched our brand new blog website (php/mysql). I don't have any idea about cyber security. Yesterday we published a topic on coronavirus vaccine. I just noticed a new post is sitting on the home page Title: "Mr.Krungzx" and user "cyberanon". I tried to search in the admin panel, but didn't find anything r...
I would like to understand better the structure of the CVE. (For example) in CVE-2018-19081, vulnerable_products mention product Opticam i5. like so: "vulnerable_products": [ "cpe:2.3:o:opticam:i5_application_firmware:2.21.1.128:*:*:*:*:*:*:*", "cpe:2.3:o:opticam:i5_system_firmware:1.5.2.11:*:*:*:*:*:*:*" ]...
I want to test out some censorship evasion techniques and want to get a connect to some censored area, such as China or so. I purchase several VPN that claims to have servers in these countries, but when I dial in, I can still visit the websites that are known to be blocked so I suspect those VPNs are lying about their...
I found that a subdomain of a site leaks all cookies of the site due to improper error handling. Now, I found that this site does not have X-Frame Options Header in it. So, I put this subdomain in the iframe tag and it starts working. However, is there any way to access the contents inside it? Or any other way to explo...
I am working for a company where vulnerability assessment for infrastructure and applications are being done by different vendors. Sometimes I get confused that assessment should happen on the infrastructure or application side. E.g. xyz application is hosted on Windows 10. Should I consider it vulnerability assessmen...
These has been fixed in later versions of Netty ... but what is the risk of using an older (can't upgrade now) version that is vulnerable to to CVE-2019-20444 and CVE-2019-20445 ... is there really a risk here? Note that the application uses netty for communicating with a 3rd party API. The app is deployed on Tomcat a...
I know .NET has two PRNGs, one secure and one insecure. What is the approach to cracking the insecure one (I want to use it to test an .aspx site)? I searched all over but I only found references to cracking the random of Java, C and PHP.
I have implemented a backend as a REST API. To maintain the statelessness in REST, I intend to use JWT to verify that that a user has logged in or not. (A user is logged in if a valid token is present in headers. Not logged in if a token is not present.) But even with expiration times are set, an attacker can access th...
I'm looking for a reference about the weird initial BCrypt text "OrpheanBeholderScryDoubt" Why was this string used? Would using 192 zeros or ones not have worked well in practice for some reason? Was that just four random dictionary words (orphean, beholder, scry, doubt), or is there some special meaning to the bcryp...
I'm trying to put together a ROP chain. I'm looking for a gadget to do the following: mov rdi, rdx ; mov rbp, rsp ; ret; But instead, I have a gadget like this : mov rdi, rdx ; mov rbp, rsp ; jmp 0x8109b3f7 So, I thought maybe I can use this gadget, all I have to do is pointing this jmp address ( 0x8109b3f7) to th...
I have a question about protecting myself against attacks on the RDP service. I note that I have already done the appropriate configuration: I am using a local user (not administrator) to connect the administrator group is excluded from remote desktop users the RDP service port is changed Local Group Policy Editor - ...
Right now I am redirecting all local network DNS traffic to my Pi-hole install, since some device do or may in the future use hardcoded DNS servers to bypass filtering. Since DNS-over-HTTPS and DNS-over-TLS are becoming more common, I would like to know if it is possible to intercept that kind of traffic to redirect it...
I am working through a report of an automated vulnerability scanner. One Item is Web Server Misconfiguration: Insecure Content-Type Setting ( 11359 ) It's about not returning the character-set for a given HTML page like so, for example: HTTP/1.1 200 OK ... Content-Type: text/html; charset=utf-8 ... the reported res...
I was reading this question: Where do you store your personal private GPG key? I have my set up as noted in this comment: Where do you store your personal private GPG key? But instead of using a cloud provider I use my own, self hosted cloud-like syncing service. I notice some downsides right away: my keys are still o...
I have recently discovered a Buffer Overflow vulnerability that leads to Remote Code Execution. However, due to the structure of the application assessed, a lot of so-called 'bad chars' came up. The list is as follows: \x00\x0a\x1a\x0d\x22\x2f\x2a\x26\x2e\x3a\x5c\x41\x42\x43\x44\x45\x46\x47\x48\x49\x4a\x4b\x4c\x4d\x4e\...
Can I register an SSL certificate that will only start to be valid in the near future and not right away?
With the Coronavirus happening, employees use remote access to work remotely from not organizational laptop access to their VDI or remote access machine via company's web portal (e.g. SSL Portal VPN). I was wondering if the laptop is infected with malware, what are some of the malware-based MITM attacks that compromise...
I've been searching about VPN for more than an hour, and all the answers I found on this site or others are either confusing or contradicting. My issue is that I usually access my company VPN through Cisco AnyConnect Secure Mobility client from my home computer. A colleague told me that they can "monitor" my home compu...
Tools like wpscan are out there in the open, which make the scanning of any WordPress website plugins without any authentication and receive sensitive data like wp-admin login names (which usually contain PII), plugins used, etc. Is this exposure of this info done intentionally or not?
The BodgeIt Store is a vulnerable web application for studying web development security. It can be downloaded from the internet and installed locally on your computer as a docket container. This web application runs on your own computer through Apache tomcat on port 8080. You can go to http://localhost:8080/bodgeit/ to...
When I access https://example.com on my company's laptop that has a X509 client certificate installed, using my home internet connection, without using a VPN, the requested page is signed using the company's Root CA (which was distributed to my company's laptop through group policies I assume). When I access https://ex...
I'm very new to Nmap. I'm using Nmap to find open ports of an IP by this command: nmap -v -Pn -p 1-100 "$ip" -oG - Here is the output: Host: IP Ports: 6/closed/tcp/unknown 19/closed/tcp/chargen 20/closed/tcp/ftp-data 21/open/tcp/ftp 22/closed/tcp/ssh 23/closed/tcp/telnet 25/open/tcp/smtp 32/closed/tcp/unknown 50/clos...
I'm logged into my school Google account at home. Can what I search at home on my own computer be checked by my school even though I'm not using their computers?
I am writing an Android application that needs to verify that a request is sent from a trusted party (me). This is my current solution: Storing keys: Generate ECDSA public key / private key from a server. Store private key in server. Store public key in Android app, hard-coding it as a static final String. Deploy Andr...
I ripped a few videos from YouTube (using y2mate) about a week ago of guitar lessons from a player named John Redbourne in case they disappear. I saved them on my local hard drive in a folder called "Redbourne Guitar" and the files are named after after the songs, like "Salisbury.mp4" etc. Anyway, I just watched one o...
I cannot do anything about government agencies, but I doubt that they are interested in me. I do not like the idea of Google, FaceTweet, etc, compiling data on me. What's the best way to prevent them doing so, if I purchase a smartphone - buy a pay as you go (unregistered) SIM, or use only public WiFi? Would a Linux 'p...
Does Whatsapp/Signal/Telegram have a backdoor access to my message which is a copy of my private encryption key?
<script type="text/javascript"> window.RPM = {"debug":false,"env":"user input"} </script> user input can be inputted with xss payload. Filter is doing following replaces: i) " with \" ii) \ with \\ iii) / with \/ I have tried with: window.RPM = {"debug":false,"env":"u</script><script>alert(1)<!--"} Replaces t...
I came across this warning message in chrome after I executed a command in the browser inspector, and realised this question had been asked on stackoverflow here but the answers do not contain so much information. DevTool requests full access to YOURPATH, make sure that you do not expose any sensitive information Wha...
I'm running a node application which needs to make calls to a third party API, on behalf of my user, using their own API keys. API calls only need to be made on behalf of the user while they are logged into my site. Currently I use bcrypt to hash and compare their password: bcrypt.hash(req.body.password, 12, function ...
We have a system where if you forgot your password and want to reset it, to go to the forgot password page and enter your email address. A temporary link will be sent to your email to reset your password. Now, when we subjected our app to penetration testing, an issue was found: Application is giving clues of possible...
The pre-built hardened linux kernel proposed by ArchLinux has disabled hibernation. The maintainer of the package commented on this choice: […] having this enabled allows replacement of the running kernel given certain circumstances and access as it suspends the state to disc. What are the "certain circumstances" he ...
I have an iOS app with certificate pinning to two different servers. I want to test this certificate pinning with a MITM attack, so I did: Set proxy at my PC, in macos wifi settings -> advanced -> proxies -> enabled http/https proxy. Installed Dynamic SSL cert on simulator. It works, I can see https data when I open s...
Is using a numeric password (similar to a PIN code on a phone) on Macs reasonable for regular users, considering they are the norm for passcodes on iOS devices? Traditionally user accounts on Macs have been expected to use passwords which include letters, digits and other characters, to make the password harder to gues...
I'm currently developing an app, which the users will store sensitive data in, and this data will be stored in the internet (I'll use Firebase or a similar service). I'll try to secure the data as much as I can (and send it via a secure connection or something), but by all means I'm a complete beginner in information s...