IT Security Stack Exchange
IT Security Stack Exchange

Questions tagged [zip]

An archive file format that is used to bundle multiple files and folders together that may have been compressed.

93 questions
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How to detect zip file encryption algorithm

As we know zip files supports a simple password-based symmetric encryption system and some vendors use other algorithms. I used the zipinfo command in Linux but it doesn't say what encryption algorithm is used. How can I find that out?
arman
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Approaches to cracking an encrypted zip file

I'm taking part in a capture-the-flag exercise; the level of difficulty is competent, but non-expert. I'm not a security practitioner, but I do have a development background and a reasonable knowledge of standard tools and techniques. One task…
strmqm
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How can I tell if a zip file uses the 7-Zip exploit?

Let's say I have a "corrupted" zip file from a potentially suspicious source, and that at least one person has attempted to extract it. Conventional wisdom used to be that bad stuff™ didn't happen from unzipping a file, but could from interpreting…
Michael
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Are .zip files used as a modern attack vector?

I recently advised someone to share (publish) a bunch of files by just posting a .zip somewhere, but realized this may look malicious to a recipient. This suspicion might be driven from Windows 95 or 98 era, where zip files were frequently…
djechlin
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Can I properly make password-protected 7z archives secure?

After reading the question and answers of this and this, I left with an overall impression from the last one that zips were considered not safe and insecure way of sharing data. I still think password-protected compressed files can be made secure.…
Strapakowsky
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How to protect websites against ZIP bombs and reference bombs?

A Zip bomb (concept here) seems quite a "smart" and easy vulnerability to websites where uploading ZIP files is allowed. Such sites are under a threat (at least to make some degree of damage to them) - someone uploads i.e. a 100 KB file [ 50 GB…
T.Todua
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Is it safe to click on zip or rar file?

Sometimes I'm in dilemma when I want to open archive file if there is any risk by opening it, because I'm not sure if attacker can use any trick that will trigger malware just by clicking on it. I'm not talking about clicking or opening what's…
user134969
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How safe (for privacy/security) is ZIP for file encryption of backups on a flash drive

I am looking to encrypt files on a flash drive (for backup) just in case it gets stolen or lost. I don't want to install any extra software like TrueCrypt but instead just use what's already there on most computers. 1) I can think of using 7z/zip…
T t
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Is it possible to read a text file inside a password-protected zip file without the password?

I have a text file (.txt) compressed in ZIP format protected by a password. I think it has only one line of text and I want to see the contents of this file. I tried fcrackzip but I think the password is more complicated than I imagine, so the…
Julián
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Is storing an encrypted zip file to an insecure cloud service an admissible way of securing privacy?

Consider the following scenario: I use a cloud service that is not considered secure (meaning no encryption whatsoever) i.e. Dropbox, OneDrive, Google Drive etc. In my account I have a .zip or .7z file that is encrypted using a very strong…
Aventinus
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Encryption Using 7z or Zip File

I'm wondering which encrypted 7-Zip file format has better encryption: 7z with 256 AES or zip file with 256 AES? Assume that a strong password is used, then which encrypted 7zip file format has stronger encryption to encrypt info in a text file?
J. A.
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What are some possible uses of a zip bomb?

This article claims that zip bombs cannot be used today as modern systems are too smart for it and no victim is going to slowly unpack terrabytes of data so zip bombs are basically useless. Is this true? Are there any uses for a zip bomb at…
Vegeta
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How does a zip file detect a correct password?

When extracting files from an encrypted zip archive, the user is asked to give a password in order to read the original file. How does an encrypted ZIP detect when the user has given the correct password? Obviously it does not connect with some…
CodyBugstein
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Are there valid reasons for compressed files (zip, gzip, etc.) to spoof file size?

Zip files, GZip files, and likely others, include information about the contained file, including the uncompressed size of the file. However, when extracting these files the number is meaningless as the actual data can be much larger (eg: reported…
Tarka
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Is a ZIP file password easy to break?

I thought that ZIP file passwords were a fairly decent protection. I came across this video, that seems to indicate otherwise. https://www.youtube.com/watch?v=SqRSNuJSm4o [12 minutes view time] Synopsis: The guy uses a zip2exe program to create a …
mcu
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