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Questions tagged [cipher]

20 questions
29
votes
1 answer

How to wipe unallocated disk space in Windows

Due to the nature of how filesystems like NTFS work, files that are deleted "permanently" from within Windows aren't immediately deleted - they're simply marked as deleted from the Master File Table (the hard drive's index) and therefore…
Hashim Aziz
  • 13,835
7
votes
3 answers

Can Windows 7 cipher.exe securely wipe USB drive?

Using the command line tool cipher.exe built into Windows 7, can it be used to securely wipe a USB attached drive?
muhan
  • 355
4
votes
1 answer

Windows built-in Cipher secure wipe

How secure is the bulit-in Cipher utility that can wipe out unrecoverable data on old harddisk?
James
  • 41
  • 2
2
votes
2 answers

Lorex DVR fails sending test email to a Synology MailPlus SMTP server using an ECC Let's Encrypt certificate

My objective & issue I want to have my Lorex DVR use my Synology NAS MailPlus Server to send email notifications, but there is a TLS connection failure, seemingly due to ciphers (tls_post_process_client_hello:no shared cipher). What works The…
info_dan
  • 41
  • 7
2
votes
2 answers

SFTP using Ciphers and Key Exchange

Previously I was gaining access and transferring files (SSIS execute process task) with a .txt file configured as: option batch on option confirm off open sftp://Username:password@hostsite.com:22 -hostkey="ssh-rsa 2222…
Kim Avery
  • 31
2
votes
1 answer

Windows 7 EFS, where are the FEK stored?

I feel confuse, I read from many technical doc from Microsoft and wiki. The FEK is generated for each file, and store in the file headers. But refer to this blog windows-7-how-to-use-cipher-exe-a-critical-win-7-security-tool The blogger say they are…
user193372
1
vote
1 answer

How to disable CBC ciphers in Firefox

The ssllabs.com browser check shows a list of cipher suites supported by my browser. Some are labeled as WEAK, I think because they do not support perfect forward secrecy. I can disable some of them by going to about:config, typing in ssl3, and then…
Roman
  • 143
  • 8
1
vote
0 answers

Allow specific weak cipher in Chrome

I have to connect to a system that uses a weak TLS cipher : TLS_RSA_WITH_AES_256_CBC_SHA. This is an embedded web server in a physical appliance and there is no firmware available to change that cipher. The only solution provided by the manufacturer…
Jereck
  • 11
1
vote
2 answers

Cipher + Public key - S/MIME implementation on MS Outlook

I'm trying to understand the S/MIME implementation, and maybe I'm wrong. I'm so stuck that I will try to explain ... Sign a mail works as I thought it would work. But, I supposed that when you send a ciphered email, you're using the Public Key of…
Morcilla de Arroz
  • 151
1
vote
2 answers

Windows 10 TLS/SSL weird issues (BAD_MAC_READ, programs queries interupted, ...)

I recently finished to assemble my new PC and installed a Windows 10 Pro from the Microsoft utilitary tool. All went fine, but suddenly, after like a week, errors began to pop in : On Firefox (latest stable version 73.0), queries over HTTPS is…
Alex
  • 133
1
vote
2 answers

What's the most secure cipher for ssh that can send files at USB3 speeds? (~480Mbps)

I have a gigabit connection between my PC and my server (iperf3 tests show ~930Mbps) and I want to be able to transfer large files as fast as possible. The hard drive on the server is connected via USB3 and it is a Rock64. With ssh (I am using btrbk…
dwf
  • 11
1
vote
1 answer

How to Zero out free space on a pen drive on Windows?

I am looking for commands or methods whereby I can just write all zeros to the free space on a Pen drive on Windows OS. The existing files should not be affected. There's a built in command called 'cipher' but it runs in 3 passes, first 0's then 1's…
rajeev
  • 1,984
0
votes
1 answer

How to include key exchange algorithms required to connect to router using OpenSSH client?

With OpenSSH_8.9p1 for Windows, I'm trying to connect to a NuCom router NC-WR764TGV: ssh user@192.168.1.1 Output: Unable to negotiate with 192.168.1.1 port 22: no matching key exchange method found. Their offer:…
jamacoe
  • 184
0
votes
1 answer

How to check which ciphers are included in "HIGH" ciphers constant

From the documentation I found HIGH "High" encryption cipher suites. This currently means those with key lengths larger than 128 bits, and some cipher suites with 128-bit keys. The sentence "and some cipher suites with 128-bit keys" is a bit vague…
szydan
  • 111
0
votes
1 answer

Rename files with symmetric cipher

I would like to batch obfuscate file names (not file content) with a simple symmetric cipher. So that I can rename them back afterwards. For example, using the online blowfish encryption on http://sladex.org/blowfish.js/ with key "hello", ECB cipher…
Dr Ljotsson
  • 103
1
2