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I have no cyber security knowledge whatsoever, and am trying to safely store passwords in a database. I understood I need to use salt, to avoid rainbow table attacks and to make sure two users with the same password will have different password hashes. However, does the complexity of the salt matter? I was planning on ...
It is known that ISP has to log various network data for various purposes, such as law enforcement needs. However, what are some examples of software tools used by ISPs to browse this huge amount of network logs? In addition, how time-consuming is for ISP, for example, to look for a user behind a given IP address if th...
I'm running aircrack-ng version 1.6 on Live Kali. I noticed that "recently" a -N option has been added for saving a session, which can be later resumed with the option -R. However this seems to have the following issues: the created session file is 0 bytes long almost always, I'm unable to stop (quit) aircrack e.g. tr...
Having the following pseudocode executed by a superuser, is it safe to assume that it is secure on Linux? if fork() == 0: # drop privileges to an unprivileged user, let's say "nobody" # perform various tasks, start other processes as "nobody" # communicate with parent process through unsafe means, e.g. Python ...
I have purchased AVG's premium service to use on a Windows 10 operating system, but it almost seems like since I have gotten it, (had it for about a month now) it keeps alerting me that it has blocked someone from remote accessing my computer. These alerts seem almost random in time but looking at the logs shows multip...
Ok, I fully admit this might be in the realm of paranoia, but hey, isn't that sort of the name of this game? :) I'm staying in a hotel room and needed to buy a small, cheap laser printer for some printouts I need to do. After shopping far and wide, I decided the Pantum P2502W fit the bill perfectly- tiny footprint and ...
I want to implement role based authorisation in my TLS connections. I.e. when my client authenticates with the server I want them to have certain privileges based on their role. Are there any provisions in the TLS protocol which facilitate this? Thanks!
Consider following C code snippet: void barfoo (int authstatus) { char packet[1024]; fgets (packet, 1023, stdin); if (authstatus != 0) system (packet); else syslog ("Not authorised to process packet"); return; } Attacker can only call this function with auth_status set to 0. Goal of...
Is there a guaranteed way to: Know there is a Remote Access Trojan in my PC? Remove it completely and successfully from my PC? Note: Assume that the hacker doesn't leave any hint of their activity (like moving the cursor). If there is no way to detect or remove RAT with 100% guarantee, what other ways could guaran...
I have a PKCS #12 file and want to export certificates and private key from the PKCS #12 file with openssl. openssl pkcs12 -in test.p12 -nocerts -out key.pem openssl pkcs12 -in test.p12 -out certs.pem -nokeys -nodes I want to uncrypt the key file openssl rsa -in key.pem -out uncrypt_key.pem But if I want to validate ...
Is there a way to add/enable ECDHE-ECDSA-CHACHA20-POLY1305 and ECDHE-RSA-CHACHA20-POLY1305 ciphersuites on Windows Server 2019 (Build 1809 or later) for HTTPS configuration of IIS webserver? According to the TLS Cipher Suites in Windows 10 v1809 (unfortunately, this page does not explicitly mentions Windows Server 2019...
I have recently seen a web application that, while using Authorization header, accepted multiple Bearer keywords followed by a valid JWT token. For example, all of the following headers would result in correct authentication: Authorization: Bearer jwttokenhere... Authorization: Bearer Bearer jwttokenhere... Authorizat...
I have enabled multi-factor authentication for my Gmail. When I need to log in to my mail, I should enter an OTP which is sent to my phone number. I got a call from this number, even though I did not sign in to my mail, and it said "Your verification code is ******". Does this mean that my account is at risk? I have ch...
I've downloaded a book but by default its considered malicious by me. I thought of converting that PDF to JPG here: https://smallpdf.com/pl/pdf-do-jpg Then backwards: https://smallpdf.com/pl/jpg-to-pdf Is converting PDF to JPG then backwards via web services considered a method for obtaining a safe PDF?
I was doing an exam and answered "true" to this question but the augrader said it was false TLS derives a session key from the agreed master secret. That key is then used during the TLS session for encryption and authentication of the session data Is this an error or is it really false ?
I am creating a file that uses Socket for exchanging data. When I use Python I have a firewall pop up where I am asked to accept the use of the application, but when my C++ program tries to do the same, the firewall doesn't warn me. My question is what differs in both cases? Is it the language? I run it on Windows, and...
Type Ctrl + Shift + N. Then type DIVIDED WE FALL and then click enter. Click a search result that takes you to YouTube. Go back to the search results. Retype "DIVIDED WE FALL by Valarie Kaur". Click enter. Click on the result that takes you to Vimeo. You see the full documentary there and watch it. If all this were don...
Contents of government gazette, Linux distributions, Open Data, etc. are public, there are no constraints for "increase user privacy". On the contrary, we want to guarantee transparency... But all tutorials and explanations about DNSSEC are also about internet banking and user privacy: is possible to separate concerns...
First, some excerpts from the CVSS official docs. According to CVSS 3.1 Specification: While the Confidentiality and Integrity impact metrics apply to the loss of confidentiality or integrity of data (e.g., information, files) used by the impacted component, this metric refers to the loss of availability of the impact...
getapassphrase.com is a website that generates passphrases. The user sets a complexity in bits, and the site spits out results like: liberal panda and ill asp decline young suit in Kansas or rowdy whale and tired DJ build brown harp in Berlin (For 64 bits, they all pretty much seem to follow the pattern of [adjective] ...
khgpd://zpn.xddspbx.nrf/j/9djwth14tmct9tf/uzdwvrrnonv.tue?gz=0 This is an encrypted text and is most prob a url....pls decode it or tell me which cipher is it, this is not for any security breaches and it is a hint in a cryptic hunt
Summary: Certificates calling to OCSP Responder (OCSPr) have their "Cert Status" change from "good" to "unknown" with no known to changes to environment. Completely lost on this one. More Detail: I have been building a simple suite for Certificate creation and OCSP handling for local and personal certificate testing an...
I want to prevent my daughter from accessing YouTube while she's attending school. So I was thinking to add protections in iptables. Unfortunately, when she goes to YouTube, the DNS resolves to IP addresses which reverse lookup to 1e100.net (which is owned by Google, no worries there,) so... a reverse lookup block is n...
Instead of collecting various logs into the SIEM, can a full packet capture solution be better in terms of having to manage so many log sources?
The BBC reports that the image Boris Johson posted on Twitter to congratulate Joe Biden contains traces of the text "Trump" in the background. The BBC article links to a Guido Fawkes' article, and when I download the tweet's JPEG, convert to PNG with macOS preview then subtract a constant background, there it is! When ...
My company is using on premise DMZ proxy servers to limit internet access to employees working from home. When they use company laptop, they are automatically configured to go through the proxy server for all traffic. The proxy will then block access to malicious and other unwanted site. This solution works but is very...
How do I make sure everything of mine is keep private? Everything from what I search to passwords to Facebook to banking? I'm pretty sure I've been hacked in the past considering I can no longer get into my old accounts
I understand that many open-source projects request vulnerabilities not to be disclosed on their public bug tracker but rather by privately contacting the project's security team, to prevent disclosing the bug before a fix is available. That makes perfect sense. However, since the code repository of many open-source pr...
As an example, I have installed Anti-CSRF Scanning rule in ZAP proxy and scanned a POST request which does not verify the CSRF token value from the back end. Ideally, it is a CSRF vulnerability, but ZAP proxy scanner did not detect that. I am wondering whether I have done the scan correctly, but could not find any plac...
I am a student studying information security. Recently I read this article link and made full exploit code. calc.exe is executed as expected. But after running shellcode, IE just crashed. (because no more code provided after shellcode...). I tried to avoid crash but could not find proper solution. What I tried is as fo...
Please note, I'm looking more for established documented best-practice rather than personal opinion in this question. I'm also not interested in Fail2Ban specifically but the class of technologies that Fail2Ban is a member of. Fail2Ban et al track misbehavior by IP addresses, such as repeatedly attempting to log-in wit...
Back in the day, mostly, such injections were taking place over the server log files. Such files are the Apache error log, the Access log and more. Techniques like these have been used for years and, hopefully, they won’t work on updated systems - even if they are LFI vulnerable. Source They won't work on updated sys...
So it's unclear how much more security needs to happen at the ACS point. I can see that the IDP signs a signature that involves a certificate and private key. The SP can verify the signature with the copy of the certificate it holds. Is that all that's needed to prevent forgery of a SAMLResponse hitting the ACS? Or wil...
I notice on various documents involving the Trickbot malware, they all state that trickbot determines the infected host's external IP address by communicating with the following hosts: hxxp://myexternalip.com/raw hxxp://api.ipify.org hxxp://icanhazip.com hxxp://bot.whatismyipaddress.com hxxp://ip.anysrc.net/plain/clien...
I am fairly new to sql injections and tried to solve a little hackit to understand everything better. I wasn't able to solve one of the levels so I ran sqlmap to see what it would do. The payloads that I got looked a bit like this http://some-hackit.com/sqli/level4.php?id=0'+or+ascii(substring((select+smth+from+somethi...
What would be some security implications of a fixed pathname (although probably in a system directory when it would be deployed as a system service) rather than a relative (out of current directory)? If the answer is "it depends", how so?
First and foremost, I'm not asking for a software recommendation. I need a direction in which I should start moving. I often need to search the internet and open many tabs in my browser. Sometimes I just don't have time to think if some particular site might be malicious. I never save any pages, I merely copy some text...
An application does encrypt the data using a secrete key before the data is being written to the database to prevent the disclosure attack. However how do we verify the integrity of such data when application retrieve data from database and decrypt it? what if a privileged user (DB admin) update the encrypted data in t...
Everyone recommends to use the pre-defined ffdhe groups from https://www.rfc-editor.org/rfc/rfc7919 There are multiple sources (for example mozilla) where I can download the DH PARAMETERS file but how can I generate it with the information provided in https://www.rfc-editor.org/rfc/rfc7919#appendix-A.3?
I want to build a REST API where applications can authenticate using an OAuth2 Bearer Token, so they get access only to resources related to one user or they can access by itself accessing resources for their own application or general resources. Therefore I ask myself how to authenticate these applications when they a...
I have just compromised a computer(legal in my local environment) and want to run nmap from that host to see further inside the network. I know I can use metasploit modules like "auxillary/scanner/portscan/tcp/", but it seems like it isnt as good as nmap. I tested this by running nmap on a an ip from my computer and th...
I have an application that communicates with the server through a TCP TLS 1.2 connection. The app probably uses certificate pinning. I want to intercept this traffic. Is there any way to decrypt the traffic except extracting master secret or RSA private key? Will MITM approach (like sslsplit) work here?
Think of the worst possibility: Someone has your laptop and you are being coerced into giving them your password. Can my Linux (I'm thinking of Arch) system be configured in a way that when a specific "fake" password is entered, a script is triggered so that, for example, some files are deleted? Or maybe, given this wr...
P3P has been removed from Internet Explorer and Edge in Windows 10. Is there a third-party browser extension that, as a cookie filter, reads compact privacy policies and allows or blocks cookies based on the privacy policies? Just like Internet Explorer used to? An add-on for Internet Explorer or extension for Edge? Th...
I know of a user within my network who initiated a VPN connection within my network. What are ways I'll be able to find out the identity of user, searching port numbers? specific protocol established? I am Using IBM qradar for monitoring a medium sized organisation.
Does normal network traffic sent out by software or anything else use port scanning for legitimate reasons? I'm using psad on my linux server and am unsure if setting the auto-ban IP feature on danger level 1, which equals to 5 sent packets, would accidentaly ban justified traffic and therefor users.
How would one go about getting in contact with a popular CT logs operator's, let's say Google Pilot, and how would one get a CA root included in their log? Are there open CT logs that allow untrusted roots or don't have a root system/program?
I'm trying to crack a MySQL323 hash and I'm unable to get it done. I was able to confirm tye hash type: I came across https://www.tobtu.com/mysql323.php. I can run it as "mysql323 32.exe" [number of threads] [hash] [keyspace-file] but there is no reference what the keyspace-file should be. Trying to crack the hash in ...
I have recently participated in a CTF competition and failed in the following stage where the solution was never revealed. After a really hard job I got access to a text file that contains a really strange set of letters which should guide me through the next stage. Some of the text is: OOOMoOMoOMoOMoOMoOMoOMoOMoOMMMm...
I am preparing for a security exam and a question I failed in a practice has the following: A command line tool that can be used for banner grabbing is called: A) tcpdump B) netcat C) nmap D) Wireshark I chose nmap, but the correct solution is apparently netcat. I am aware that netcat is used for banner grabbing, but ...
If I have a web service (REST API, RPC, etc) that I open source, how can I prove to the user that the service they are connecting with is indeed the same one whose source I published. I am envisioning an endpoint they could query and get some kind of hash/signature they can validate. The problem seems that the API serv...
Recently I've been studying SMTP and I've wrote a program that uses socket programming to send emails via extended SMTP (RFC2554). As I understand, in this protocol one sends base64 encoded strings of username and password to the mail server. But since base64 encoding is not encryption, how can I ensure my username and...
yesterday one of my client's system started to popping this message, is the threat legit, what options do I have to restore
If I connect to my VPN and then run arp -a the MAC address of my router changes to 00:00:00:00:00:02. Is this normal behaviour? What is the reasoning behind this? Furthermore a MAC address spoofing is only of real concern when there are more than one devices on the network, and they try to become the MITM correct?
What are the security implications that come with loading an image in dataURL format <img src="dataURL" />? After signing into my website the browser loads an image in dataURL format for first time and take a few seconds to load. Later when I come back to the site and attempt to load the same image the image is loaded ...
Consider an application in which users will install on-premise agents which communicate with a cloud hosted service (aws in this case). The users can interact with the cloud service to configure and assign work to the on-premise agents. The cloud service will be multi-tenant, and will store some sensitive customer data...
I have an SSD with the option (with ATA-commands) to erase the firmware for security reasons. In the firmware flash cells, the secret key is stored for encrypting the data on the fly. When I ask the vendor how it is deleted, they tell me it is erased. But I would like to know "how it is erased". They tell me the cells ...
I want to know if is bad to trust the PHP's global variable $_SERVER values. I have a scenario that I change between developer and production site, and I have a config.php file. On this file, I check $_SERVER['SERVER_NAME'] value, to determine which group of constants I should use. If I'm on production environment I us...
What is the most secure way to automatically connect my remote server via OpenVPN to my home network for running a script? The plan is I want to automatically backup some folders to my Synology NAS at certain times. I assume saving the VPN username and password in a file is one of the worst ways, but on the other hand ...
I've received notice from our risk management group that they believe our website falls in scope for SAQ-D. We utilize third party vendors for all of our payment processing - and on the website essentially just provide static links (href="ourcompany.someprocessor.com") to direct them to the payment processing sites. T...
I am an application developer and am building a token-based auth mechanism for my application. Essentially, the user will log in with username+password, if the credentials are valid, my code will generate a JWT (probably going with a 30-minute expiry, at least to start with). If they attempt to request authenticated re...
I got a call from an unknown number, more specifically, a no caller ID number. I’m not the guy who gets a lot of calls from a no caller ID phone number, and usually, when I got one is typically the hospital, nothing suspicious. I know in Canada and many other countries, carriers allow us to hide our numbers without any...
I am using a couple VM's fitted with proxies and find that browser fingerprinting across VM's causes me many issues. I also have issue with the browser created inside VM leaking that I am using VM. May seem like a n00b question, but is anyone able to give insight into the best setup for using multiple VM device browser...
Is there a course or resource for a person with basic networking skills to see all ways a website like FB or Google can track and identify users + how to spoof them and look natural? Not for malicious activity just feel frustrated by the lack of information available on this online. Like, let's say I have 2 devices on ...
During the setup of a new encrypted volume, the VeraCrypt requires a random mouse movement within the window. If someone looking from the outside can see that a monkey sitting in front of a computer playing with the mouse. There are good solutions to generate cryptographically secure keys like the usual /dev/urandom [1...
This could be basic question as I'm new to this area. I have an apache web server which load balances to a set of servers to provide a web site. The apache server has SSL enabled and we terminate TLS on load balancer level. The TLS certificates lives inside the apache server's local storage. Now our target is to use so...
I'm testing burp against a vulnerable application as part of work for my client. There was one successful xss payload related to DNS lookup which worked on form data at point of file-upload. Here is the part of payload javascript:/*</script><img/onerror='-/"/-/ onmouseover=1/-/[`*/[]/[(new(Image)).src=(/;/+/7mu0war5msd...
I'm trying to understand how the hash length extension might work on real web applications using a hash for MAC. Especially what I don't get is, how the application considers the evil forged hash valid. Let's say we have an app which sends this and I want to tamper with data POST /stuff?mac=d147c7b4a79f920a1efefddc30da...
I maintain an operating system that can be deployed to embedded devices with highly diverse capabilities. One of the aspects of porting the OS to a device is declaring the available entropy sources (including, but not limited to, dedicated TRNG peripherals) which will be used to seed the CSPRNG. The security goal of th...
I know that you need to change permissions for a file to run as a script on Linux. Is that enough to prevent any malware from being installed by some self-extracting file? Is there anything that can be done to increase the security on a Linux machine? Also, can a self-extracting file be of any file format (other than a...
In the recent past I have been a victim of virus/malware attacks on my home computer running Windows 10 (Home), since I used the same account with high access rights to also browse the internet. However, to mitigate the risks I have upgraded to Windows 10 (Professional) and have also created a standard-user specificall...
Would concatenating (i.e. joining together into one string of text) a secure (i.e. Diceware) password and other, much less random, passwords be a good idea? This new password would be used as master password for my password manager, and, since it would replace all my passwords, why not concatenate all of them into one ...
Take the following examples: When I run sshd, it can in theory grant access to anything that the process itself has access to, regardless of provided credentials. For example, I could in theory modify a single if statement in the sshd source to grant access to my home directory to anyone. On the other hand, if I encr...
How does John The Ripper work when trying to crack passphrase of a private ssh key? What steps are involved when it tries to do so? What's the role of ssh2john in the whole process?
I have been reading about authentication and authorization for the past few days and I still have not figured out what would be a reasonable way to deal with this for both mobile and web applications. From what I read, when it comes to a web application, using an access and refresh (JWT) tokens seems to be quite popula...
My parents live way out in the middle of nowhere. The only service provider that is not satellite is Century Link, which uses ADSL / phone lines. They wanted me to set them up, and the service guy was trying to charge them a rental fee per month for the modem; I dug around in their "old technology" bin and found a West...
Assume we use AES256 to encrypt the same payload 100 times, each with a different key. An attacker gains access to the 100 encrypted payloads, and nothing else. Is there some way the attacker can gain insight about the payload (or about the keys) based on those 100 encrypted payloads? What about accessing 1 million enc...
I've been reading online that homebrew changing usr/local/bin to r/w could pose a serious security issue as usr/bin is the path after usr/local/bin. Article found here: https://applehelpwriter.com/2018/03/21/how-homebrew-invites-users-to-get-pwned/ Is this legit and an actual safety concern? I'm new to linux paths and ...
This question is about how to secure API keys. Not sure if this is in the same category as Key management for Cryptography and should follow the same rules. See details below. We currently have hybrid Mobile Apps. The apps are made using Angular and Ionic. Now, we have some functions where we would need to use some of ...
I was reading this question on Stack Exchange Workplace community and it indicates that an IT team was able to prevent a user from turning their laptop on (power on). My laptop access has been shut off (IT somehow remotely shut it down, it won't power on), company cell doesn't work, can't access e-mail via webmail. I...
Does a X.509 Certificate contain some kind of ID that is associated with the Private Key that was used to create the Certificate? So if i had a database of all my Private Key IDs, i could then look at a Certificate Field, that contains the ID and know which Private Key was used. If so, what is the field? And is there e...
I've installed NextDNS on my iPhone and started noticing random connection requests to *.aliexpress.com, live.musical.ly, amazon.sa, and others. What made me wonder is that I don't have "background app refresh" enabled, No app from TikTok, AliExpress, or Amazon is installed and I had the phone locked ("standby") durin...
The Microsoft ktpass tool can be used to generate a .keytab file that contains a secret key. I'd like to understand the output of the tool. An example output can be found here. I'm interested in the following part: keylength 16 (0xdd74540caa4a230af2ed75558a37995d) The Microsoft documentation is quite vague on the exac...
BIOS, UEFI and hardware's firmware ROMs are not very comforting sources for concern. On a system that I administer, a large amount of main system memory (9 of 512GB) is unavailable. Next to the unfortunate loss of a valuable resource (main memory), I am concerned with the question how to evaluate this "opaque" memory t...
I just got a message from a security guy that my application is executing remote code if they pass a Content-Type: image/asp. For now he does not disclose anything. Now my question is that if I am using ASP.NET 5 MVC application using IIS webserver on Windows Server 2012 R2, can you send a specific content-type to web ...
I'm using a free template as a front end in my application and the main javascript file came out as a high risk as it's vulnerable to a dom based cross site scripting.Is there a way to sanitize the javascript function inside a javascript file? I searched and i found a .net library "System.Web.Security.AntiXss" that wor...
I have a IPv4 network behind a pfSense firewall at my small business. We have around 200 IP devices on the network. We have about 30 Axis IP cameras which have MJPG streams embedded into webpages as img tags. The webserver is internal and external facing, but we don't have a proxy for the cameras and thus only use the ...
Let's say we have: a local computer (Windows or Linux) a distant dedicated server with 2TB storage, running Linux I'd like to do a backup my local computer's data folder (1 TB) to the distant server (updated every week of a few GB), but I have a very specific requirement: I want that that even if a hacker gets root...
Background As many others I am working from home and we use a VPN to access services from the company intranet (SMB fileshares, git repo, project management etc). To improve things like video calls I suggested to our IT to enable split tunneling to allow traffic not determined for the company intranet to use the home i...
I'm planning to donate a laptop to a school, for kids to use from home during the pandemic. It's my previous work/development laptop, so I want to erase the drives as securely as possible (within reason, I'm not exactly expecting a state sponsored attack.). But keep them in good working order. There's both an HDD and S...
X-Frame-Options HTTP header is used to tell if a webpage is allowed to be used in a frame/iframe. Frames can be used for click-jacking/UI-redress attacks. It is advised to set X-Frame-Options to 'DENY' to prevent page being used for click-jacking. But, is it not possible for the attacker to tamper the headers (esp...
I use opera browser, and while the built-in VPN has been working relatively well it's been preventing me from joining discord voice calls and using omegle. Is there a way to hide my activity from my ISP without encountering those problems?
I don't have an instagram account, but I always look to my friends' profiles on instagram or mystalk and see their stories. BTW my google account is always signed in when I check their stories on instagram or mystalk. So my question is: in what cases they will know that I see their stories? For example, can they know (...
I'm working on a centralized exchange for cryptocurrencies. the approach that I'm taking for some reasons is to create an account(private key) per user inside platform. so these accounts should be controlled by platform. now my problem is how to safely store private keys in server and then safely retrieve them for sign...
How do I hide my ip address if I use a wallet as coinomi? Do I have to use Orbot? If yes, what exactly should I do? (I'm using it from an android) I just want to have privacy when I log into the wallet. I want to hide my ip when logging into it.
A typical scenario: a big company with lots of servers in all shapes and colors (on-premise, private and public cloud) Each server (or rather each service) needs to maintain a trust store (a file in Java, or a file folder in Node.JS) that contains certificates required to establish SSL/TLS connections to other (mostly ...
I've created my own CA with openssl. The problem I'm having is that when I sign a CSR and generate a PEM certificate with it, there is an initial text portion in the certificate where I was only want the actual encoded certificate itself. In other words, the output certificate begins Certificate: Data: Vers...
ISO 7816 smartcards are typically used in EMV transactions. I know that the card can perform arbitrary actions before sending a response to the terminal in a typical EMV transaction (e.g. signing dynamic data to generate SDAD). However, is it possible that the card perform a certain action while waiting for a command A...
When I did my degree ~20 years ago, the contents of an email were described as being "as secure as a postcard". Since then, HTTPs has become standard for web browsing and the absence of security is noteworthy; have equivalent changes occurred with email, or is email as bad as it ever was? (Target level for answers: I h...
In our web app the users can specify a URL that the server will access later (POP3 access and browser push notifications). This means the web app does a network request to a user-chosen server. The web server might have access to parts of our internal network or some services might be running on localhost. ...