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I have a verification certificate signed by my organisation’s CA, which I can use to authenticate my user account on intranet web services. Is there someway I can sign a new certificate which can only authenticate to one specific web service. Or some other way to enable limited access to one web service by a script I d...
I have an external server make backups of my main server via scp and a backup-only user account. I successfully restricted it to scp only using GNU Rush. The scp command below executed on the backup server downloads /var/www/website1/file2 from the main server. scp backupuser@example.com:website1/file2 I want to make...
I'm trying to learn a bit more about the different types of attacks but as far as I understand it, a rainbow table is a large collection of prehashed data which is then compared to hashed data gathered from a target. A dictionary seems very similar but I'm struggling to find anything that can specify the differences be...
As I understand it, the Same-origin policy (SOP) basically prevents a script in a web page from obtaining or sending information from/to a different domain. I understand that this is important to prevent a page from grabbing private data and passing it along somewhere else. For example, without the SOP, I could write a...
Do AWS EKS managed nodes receive security patching automatically or is it the owner's responsibility to patch?
What is the recently patched and disclosed Windows 10 OS family Crypt.dll vulnerability CVE-2020-0601, nicknamed ChainOfFools and/or Curveball? I've read up on it and while I understand the basics (deriving an alternative private key from a public key through manipulating cryptographic algorithms so you can spoof a cer...
How can I list all signatures made to a public OpenPGP key without importing it? A file with the public key is available. I would like a similar output to gpg --list-signatures <key-id>, but instead of using the keyring, giving a file. I have tried gpg --list-packets <file> and pgpdump <file, but both outputs are not v...
I'll quickly outline the purpose of our application: The user logs in using his username and password. He will receive a list of servers he can connect to. After choosing a server the connection to this server is established. Some more details about the application that complicate our requirements: One user can have m...
I configured a Windows CA and created a certificate template to issue certificates with ECDH_P384 keys: Then I noticed that it's not possible to set the "Key Encipherment" key usage in the "Extensions" tab: What is the reason behind this limitation? Is it correct to say that the "Key Encipherment" key usage makes no ...
I’ve recently bought a new HP Pavilion laptop, it came with pre-installed software (bloatware) such as various games and other useless stuff. When setting up the laptop, i was connected to AIS, which is Thailand foreigner mobile network. I have immediately took an action and deleted all bloatware except preinstalled HP...
TL;DR: Is it possible to have both sides of a SSL/TLS connection have the same public and private key, so long as that public key is trusted by both sides? More info if helpful: I'm trying to test how I'd setup having Java application connecting to Kafka 2.1. I am using the same keystore and truststore for the Kafka cl...
It appears to me that apps like Whoscall and CallApp might access your photos and such. In case of a potential data breach/hacking in one of these apps - how can I delete my info from their servers?
I've recently written a simple keylogger using classic DLL-injection technique. I wanted to simulate a real phishing attack where the user opens an Office document with macros and by enabling them he downloads and runs my keylogger. While the keylogger itself is not being recognized as a thread, the VBA script is. I've...
Also directly related, how are the DNS servers queried when using proxychains? Assume I'm using Tor for proxychains. If I uncomment the DNS part of proxychains.conf, my requests supposedly get sent straight to the Tor network. If this is the case, how is DNS resolving done? At what point? Does uncommenting that line in...
From what I can see, most firewalls seem to focus on tcp and udp. Why is that? Is it impossible or at least very unlikely for malware to use other protocols/custom protocols?
Let's say there is file which successfully passed all scans by all antivirus software there is on VirusTotal. Does it mean that it can't be dangerous. If no, what kind of dangers we can expect?
The https://www.rfc-editor.org/rfc/rfc5246#section-7.4.9 states which messages are included for PRF computation that is included in Finished messages It is clear for 'regular' (initial) handshake But assume that the client wants to resume the DTLS session Client sends the ClientHello with previous SessionID field The s...
As client I am using an API of a company. To be able to connect I have to decrease the security level to CipherString = DEFAULT@SECLEVEL = 1 in /etc/ssl/openssl.cnf using OpenSSL 1.1.1d. Then if I do openssl s_client -connect <servername>:443 I get: ... No client certificate CA names sent Peer signing digest: SHA1 Pee...
I have newly bought HP Pavilion laptop, which i am planning to nuke and reinstall. I really do not like the bloatware as it might posses a security risk. However, in Thailand, i do not trust the sellers of USB sticks and external hard drives, i do not want to infect my laptop with that. (BadUSB etc.) What can i do? Is...
Is there any standalone patch for CVE-2020-0601 (CRYPT32.DLL exploit) besides installing Windows 10 latest cumulative update? Or is there other ways to mitigate this exploit, when immediate patching with CU isn't possible?
News coverage of this makes it sound like the NSA is mending fences and helping us all out, kindly and heroically. I have nothing against the NSA but isn't it more likely an adversary has been exploiting the vulnerability and they are disclosing it to mitigate that entity's effectiveness? Still a public service perhaps...
I'm doing research on certificates and I've managed to find a dataset. It is a single large text file where each line appears to be a PEM encoded certificate but I am unable to load them using pythons asn1crypto.x509 although I am able to load my own captured certificates, here is an example: bf55348d696395689d5c461bc0...
Imagine an app where any user provides a username and a password. This password is used to generate a 'strong' encryption key (for AES encryption) with the PBDKF2 key derivation algorithm. This encryption key is used to encrypt user data in a database. Now, to identify a user and grant him access to his encrypted data,...
Under the authorization of my friend, I am testing his website against potential vulnerabilities. I was trying to find if I was able to inject a SQL query into a POST request parameter hi' or 1=1 --: query=hi'%20or%201%3d1%20-- I found that the document prints out: <div class="error">index job,query: syntax error, une...
I have setup a local apache server with php module.I deployed a dvwa in my localmachinne..I am learning about XSS(DOM) type of attack.I setup the low level security in dvwa.When i added <script>alert()</script> in the url i got an alert http://localhost/dvwa/vulnerabilities/xss_d/?default=English<script>alert()</scrip...
Can my isp see the (non-https) websites I visit if I use browser VPN extension? Chrome notices non-secure connection for them but I use browser based VPN extension and different country (VPN server).
I have a web application built in a classic MERN stack (MongoDB, Express, React, Node) and I want to create an admin route, so I figured I could just do it with a [url]/admin route. Could that be a security risk? Of course the admin users would be prompted with some form of authentication, but having the admin panel a...
My dad sent me this video asking if he should be worried about this? The video shows: a wifi AP broadcasting an airport's wifi name security researcher seeing the sites the victim browses security researcher viewing files accessed by victim on cloud storage victim installing attacker's "free wifi" app the app giving t...
Let's say I have a TOTP generator app (like Google Authenticator) installed on my smartphone. I use it for 2FA for service X. How bad is it if I log in to X's website/dedicated app on the same smartphone? Would I gain anything by using an airgapped phone dedicated for TOTP?
I get this in logwatch A total of 21 sites probed the server 1.144.111.208 123.31.43.40 174.216.5.13 185.156.177.234 188.175.196.105 188.71.236.121 197.229.2.33 197.229.2.44 197.229.2.89 223.206.234.87 69.123.106.157 71.80.149.79 73.240.179.91 73.25.58.45 73...
In the Asian Saga series by James Clavell, the Struan family gave away the half-coins of Jin-qua: in exchange for a desperately needed loan, the pirate Dirk Struan received 4 halves of 4 coins. The Chinese merchant, Jin-qua, kept the remaining halves. The repayment of the loan came in the form of an oath: Dirk Struan ...
When you use a cellular connection how is your internet connection encrypted? Usually there is some sort of key like with WIFI the wifi password is the key used to encrypt data? How does encryption work on a cellular network when connecting the the internet? Does it use the AT&T password on your account? For example if...
I understand that generally email communication is insecure by default and would like to know if its possible to setup email servers so that the emails get encrypted when sent between hosts. I want to know if there is actually a way to include personal information in emails and keep it secure in a Business to Busines...
Background: I have an Android APP with millions of users, but some users are malicious users (robot, fake, privilege escaped, etc). The common solution is to detect & block those "bad" accounts controlled by hackers. But, here, I aim to detect & block those hardware controlled by hackers. In another word, "fingerprint"...
I have a REST API exposed to the Internet and another application with form-based authentication. These apps are behind a Web Application Firewall. Question is, where I should implement the below security HTTP headers, in the WAF or at the code level? X-XSS-Protection X-Frame-Options X-Content-Type-Options X-Permitted...
I have an application that needs to store Network Credentials for a Network Drive/Share on the disk. The user shouldn't need to enter the password every time. The OS is WinPE, so he cannot map the drive once and it will stay there. Limitation: I need the password in plain text, to map the drive. The program should wor...
For example : Nordvpn provides both chrome extension and its desktop software. Opera provides a free browser vpn, etc.. Some people says the browser extensions may leak dns but i never had an experience with it (by dns leak tests). What about them on http:// (non https) sites? Is the ISP can see what websites we visit...
I'm running a scan with Nikto. The command I'm running is pretty simple: nikto -h 192.168.1.15 -p 5050 It's a Node.js server. But I get a gazillion vulnerabilitites, for instance: OSVDB-19947: /apps/web/index.fcgi?servers=&section=alert(document.cookie): Zeus Admin server 4.1r2 is vulnerable to Cross Site Scripting ...
Recently when I was changing some Amazon account settings, I've noticed that they provide an option to validate the OTP by appending it to the password. How would this work, if the password is one-way hashed?
If you connect to https://google.com (without www.) you get a HTTP 301 redirect to https://www.google.com/ . Then if you connect to https://www.google.com/ the response includes the strict-transport-security header. I contend this is a (small) security gap, because the strict-transport-security attribute never gets se...
I have some questions about encryption in java as I'm trying to develop a password-manager-like application for my final test in Computer Science in High School (Germany). The password manager uses a server with a REST API to save the passwords in a database to transfer the passwords encrypted to the user where he migh...
Have I fundamentally missed something between the time when I sat with my 486 IBM PC in the house, fully offline, and today? Do normal people actually set up complex local networks in their homes where they have some kind of "trust anyone with an internal IP address" security scheme going on? What does "gaining access"...
In my company, we have two internal domains with a firewall between them. When requesting firewall rules for an application with components on domain A and domain B, I was told that encrypted protocols were not allowed through the firewall. (e.g. HTTPS 443, SSH 22). The rational was that hackers could potentially tunn...
There are sites like grabify and iplogger.org which allow you to get the IP of the person who has clicked the link. Logs are also generated by various bots when you send a message via Twitter, WhatsApp, Facebook or Instagram. Will it be possible to get the IP of the individual without him clicking the link? An example ...
So I am trying to extract data from a full memory dump (Made with either dumpit or a BSOD). WinDBG manages to extract some information from it, but Volatility is silent: PS F:\> C:\Python27\python.exe C:\Python27\Scripts\vol.py -v -f .\DESKTOP-1NHUJ5K-20200115-133054.dmp imageinfo Volatility Foundation Volatility Fram...
I've done some researches on this topic, and I found this question on SE: Sending session cookie inside the HTTP response body But this answered my question just in part. On login, my server will create a httpOnly cookie, and also put this authorization token in the response body. This is because my server handles norm...
I read about this malicious Sudo function on Nullbyte where by inserting this bash function into a victims .bashrc/.bash_profile an attacker could exfiltrate sudo passwords fairly easily. This got me thinking about other possible malicious functions, aliases, or commands that could be hidden and secretly executed here...
I just got a message today that someone changed my password on my Google account. The email seems legit, and Google confirmed there was a login from Ukraine two weeks ago in recent activity. The password change that happened today occurred in a city in the country I live (Netherlands). I have two factor authentication ...
The only 'solution' I thought of is linking a CVE to a CWE and then to a CAPEC (Method found in this link: How to find CAPEC items related to a CVE) but I am unable to get from a CAPEC attack pattern to a technique/tactic in the ATT&CK matrix. (On a side note what is the difference between CAPEC and the ATT&CK matrix? ...
In simple words: Does Bitlocker (without Pin) transforms the normal "Windows User login" into something secure? So if you activate Bitlocker (without a pin before booting) you are forced to use the original unaltered Windows installation to retrieve the key from the TPM Module. Meaning, if you try to start the computer...
I have a bunch of services which I want to group under a subdomain. Somehow 2-factor authentication is not possible to identify the users of these services. I have a thought to have randomly named subdomain to make it difficult for the attackers to know my subdomain. So, let's say I have a domain example.com and I want...
I am build a website in Angular which communicates over my REST API on my backend server. I have managed to auto-generate the code (TypeScript) for my client and now I need it to be available on deployment. There are several ways to do this and the, in my oppinion, easiest way would be to just publish the client to ht...
I'm developing an app that will require users to authenticate via their Azure AD account. Customer would like a branded, custom UI, including the login screen. The current library for Azure AD authentication is MSAL.js. Using this library, the recommended flow is that users are redirected to the Microsoft login page (I...
Should I trust VPN services that provide post-quantum encryption like NewHope for protection against future quantum computers? How can I tell if the connection between me and the VPN is using post-quantum encryption?
UPDATE: Looking at the product again, I don't think this even has built in Wi-Fi (it uses bluetooth for the connection). I don't know what I am looking for here in Wireshark, but I added the host 192.168.40.59 and ran it for about 15 seconds and there was a constant packet that was captured, maybe a ping? I was goin...
On one of my Windows machines (so I am admin and basically can do whatever I want with it) I'd like to analyse traffic which obviously is directed to a malware C&C server. The traffic is TLS encrypted and originates from an injected/infected service which I know (so I know the exact executable file which is causing it)...
I've been playing with x509 certificates to better understand them and I've hit a strange issue which makes me think I have a misunderstanding. Initially I tested everything with libressl 2.8.3 and things work as expected, however when testing against openssl 1.1.1d things fall apart. First I've created a root key and ...
Reading papers written by teams looking for vulnerabilities using fuzzing, I notice that many people label a crash as a DoS vulnerability. While in other papers and researches, they go deeper after the crash and try to exploit it to get RCE. My question is whether all memory related crashes can lead to RCE or there are...
In the instance of a web server that requires client certificates to log in, what exactly is creating and updating the CRL? From all of the examples I see, it is a manual process. Is it really a person manually adding a certificate to the CRL when you no longer want that person to have access to the website?
I am currently in the middle of operating an analysis on Autopsy of a virtual machine (VMware) that has been hacked. I have mounted the VM and I am acquiring the evidence from VMware to my physical machine (Windows 10). I am trying to do a Logical File Acquisition of certain files and folders ; Windows Event Viewer L...
What piece of information can websites retrieve that would allow for later identification without cookies? Intro Out of interest I jumped into the rabbit hole of online marketing scams. The site I visited* used a system called Proof** to show 'conversions' (cq. signups) to visitors and I was curious if this system coul...
As we know CIA of the demand for security means: Confidentiality Integrity Availability I don't understand why define the "Integrity" and "Availability`, If we make a plaintext Confidentiality, the Integrity is a whole plaintext, this is the basic, why there gild the lily? If there defined the Integrity, the decr...
I am using the Cisco AnyConnect Client 4.7 to connect to a VPN. I need to decrypt the traffic to examine the packets and understand how VPN works. I have read about providing the PSK to Wireshark, but I can't find somewhere explaining how to get that when using this Cisco Client. Additionally, I need to do the same usi...
I've recently found out about this new technology, which recently became a World Wide Web Consortium recommendation and also that now almost all main browsers support it and it is enabled by default, see e.g. this. I was not able to find in e.g. Firefox about:config to disable it: Unlike JS: As noted on Wikipedia, ...
That is, is it generally considered more secure to save a single application-wide private key on the web server compared to storing (protected/encrypted) private keys in the database? More specifically, would storing multiple copies of the same private key XORed with different SHA512 hashes (generated using the user's ...
Previously, authentication systems stored passwords in cleartext. This made it trivial for an attacker to log in to an account if he had access to a leaked password file. Later, passwords were hashed once and the hashed value stored. If the attacker had a leaked password file he could try hashing guesses and if a hash ...
more of a philosophical question, suppose there is one behavior which allows an attacker to do something with high impact but by itself cannot be used to cause that impact. For example, internet accessible admin portal which even though still requires authentication, it doesn't have IP whitelist nor 2FA. Suppose that u...
Assume Mallory knows the server, username and password that Alice uses to send email via smtp. Can Mallory read Alice's email? Does it depend on the specific system or configuration?
I want to know whether or not it is useful to a malware researcher or AV product to use steganalysis tools to detect or study malware. If so, is there a standard steganalysis tool that's generally used or does it vary from analyst to analyst?
There is a need to encrypt data and upload somewhere on a periodic basis. We have a master key that is used to generate data keys. On each instance of upload, a new data key is generated and the data is encrypted using the key and the key is encrypted using the master key. Is it fine to store the encrypted data and th...
Im developing my first API but I think I can optimize the server response by eliminating an SSL decryption. The server recieves POST request with two parameters: Action (int value) Data (base 64 encoded) If action is valid then the data gets base64 decoded. The result string then gets decrypted by the openssl_private...
I am trying to verify the SSL renegotiation vulnerability reported for one of our URLs by a vulnerability scanner. The scan report lists the SSL Renegotiation vulnerability as - 'Insecure Transport: SSLv3/TLS Renegotiation Stream Injection' I cannot check the openssl version currently installed since I don't have acce...
When employing a system-wide VPN on a smartphone, I understand that all web traffic is routed through that VPN. Browsing to a webpage in incognito mode would provide some degree of anonymity, but I'm wondering to what extent installed apps can be trusted. I'm assuming any app can retrieve and store unique device inform...
I have been reading articles about exploits which allows someone to send an MP4, PDF or other file type through WhatsApp or other service, which self-executes to install malware without any user click or intervention. I know some of these security holes were patched by WhatsApp recently but presumably other holes remai...
Is there any advantage to me installing fail2ban on my VPS web server? As far as I understood, fail2ban's only purpose is to stop bruteforce and dictionary attacks by preventing consecutive password logins from the same IP addresses. If I have a 12 character password randomly generated and containing lower case, upper ...
I have created a service that takes login credentials and gives back a JWT. Now the JWT is created with a secret key from this service. I would like to use this token to get access from other micro-services, however on the micro-services, I would need to add the secret on there too. This seems quite ok if there aren'...
You know one of those news when someone says "thousands of users' passwords and personal emails have leaked...". It's the type of stuff that I assume would be prevented if the emails were encrypted in the app's logic, before storing them into the database, because whoever gets the database dump, doesn't necessarily hav...
The SEI CERT Coding Guidelines assign a priority to each rule, formed from the product of three factors: severity, likelihood, and remediation cost. Each of these three factors is assigned a value from 1-3, and the highest priority formed by such a product is 27. While the severity and likelihood correspond to my intui...
I found a strange behavior of Shopify, where an attacker can change the extension on a URL and the backend will send back an HTTP content-type matching that extension, for each of these extensions: atom: application/atom+xml bmp: image/bmp css: text/css csv: text/csv gif: image/gif jpg: image/jpeg json: application/jso...
Is there a way to find what type of encryption/encoding is being used? For example, I am testing a web application which stores the password in the database in an encrypted format ({"data":"myPYj0/eRAw7ZELNNmJN7FGkyXmySbVRaa9Jf1s2g8Gf7rmuhP+sEYV1n6iaaqcqc0mIoDL2xl1Gvm4Xnu2qF9NnHLN8FGJ7buGJDdq4HDTQK7I6nrTK2iBqbZDyknRTaK...
I was reading this The New York Times (NYT) article about the hack of Jeff Bezos's phone. The article states: The May 2018 message that contained the innocuous-seeming video file, with a tiny 14-byte chunk of malicious code, came out of the blue What malicious code could possibly be contained in 14-bytes? That doesn'...
I have a few VPS and Databases in GCP, I can access them by whitelisting my IP, but just few months ago my ISP rollout their CGNAT and I was affected. As far as I know CGNAT, allow multiple subscriber to have a single public IP. Is still safe to whitelist my IP or I need another means or extra layer of protection?
Excuse my ignorance as I don't work in infosec. I ran reboot inside a linux virtual machine using VirtualBox on Mac and it rebooted my host machine. I am trying to reproduce the problem but haven't gotten it right just yet. If I am able to reproduce the issue, should I report it and who should I report it to?
I'm trying to understand Yubico's documentation of the U2F standard, and getting hung up on the PIV attestation piece. The security claim appears to be that the authoritatively-signed attestation certificate sent by the device upon registration will allow the relying party (~= server) to verify that the keying material...
Consider a website example.com that allows users to upload arbitrary JS files, that are then stored on the server and served to visitors with a JS content type. Could an attacker use this to perform an XSS attack on example.com? At first, I thought the answer was an obvious yes. But thinking about it, it is not obvious...
Is an attacker able to intercept tls communication and get cleartext size information from the encrypted size of intercepted payloads? Or is there some kind of padding which would prevent messages such as yes (3 letters) and no (2 letters) from producing different size (larger for yes)?
From what I've seen, USB-based attacks such as RubberDucky need to be able to open a terminal and then execute commands from there, usually to download and then install malware or to open a reverse shell. Is this how most, if not all USB-based infections operate? Would being able to detect and prevent keystroke injecti...
We are writing our first public API. Now I remember hearing in the past that you shouldn't give users useful error messages, that allows hackers to learn what your data is. so if the get is { policyNumber: '43', product: 'car insurance' } the error message shouldn't give the user enough information to refine their s...
The Chrome WebRequests API mentions that specific request headers are not available to the onBeforeSendHeaders event, meaning that extensions cannot read and/or modify these headers. Here is an excerpt from the documentation: The following headers are currently not provided to the onBeforeSendHeaders event. This list ...
I have a list of very sensitive strings and I want to ensure that these strings do not exist in a set of documents (potentially very large documents). However, these substrings are so sensitive that I don't want the third-party performing the search to ever see or have any access to my substrings in clear text. The 3r...
I want to pass my OSCP exam and I am learning with the material I got. I watched the videos and read the pdf but I have a question about buffer overflows. In the example in the videos, the guy has access to the target system and can so control, debug and restart the application. So he can see what length he should send...
I am studying the Vigenère Cipher that given a passphrase uses rotating Caeser Ciphers to encode the plaintext. The ‘classical’ attacks on Vigenère first deduce the length of the passphrase by conducting the Kasiski test and/or analyzing the index of coincidence. To come to my initial question regarding repeated letter...
I am thinking of using IdentityServer4 for a new project. I am new to this and have done some reading and seen some of the demo clients in action. Most of the clients in the samples allow login as a User and issue a token. Requirement I have multiple applications and they are, for example, MVC/SPA/Mobile, etc. I wish...
Is this a safe way to filter strings into an SQL query in java or could this be bypassed? I understand that I should just parameterize everything but this is an ancient code base where it makes more sense to do it myself. public static String escapeSQL(String input) { if (input == null) r...
I am currently implementing an iOS app, which integrates with a cloud hosted .net backend system in azure, which. The api login endpoint takes user/pass -> replies with an signed only HS256 jwt token. All further calls to the endpoint require an Authorization header of type bearer, and the endpoint supports renewal of ...
If a website uses an auto-incrementing user-id in its url – /users/1, /users/2 to showcase public user profiles (just the name + photo / avatar) is it considered a possible vulnerability?
There is a laptop - not mine, someone else's. That someone else, as far as I know them, are a bit lousy in their security best practices (do they even have AV installed? not to mention OS patches or rather the lack of them) so I wouldn't be suprised if their laptop was infected. Thing is, they're bringing their laptop ...
When a new client is trying to get a new IP from the DHCP server, it broadcasts the discover message. And also DHCP broadcasts the offer. And they use the transaction ID to communicate without the IP address. Would it be possible for another client in the same network to send a DHCP request with the same transaction ID...
There are references in TLS 1.2 RFC 5246 about use of certificates (server and client). I am unclear about the "key usage" extension of a certificate as it relates to TLS 1.2 and that too for data encryption only. I am not not concerned about using TLS by CAs themselves. Here are the various key usage types: KeyUsag...
In my current architecture I have an authentication server which provides a JWT token via OpenID Connect to any web application that uses the code flow I implemented. I went to the hassle of implementing OpenID Connect (mainly thanks to authlib) to let the authenticated web applications being stateless. It also allows ...