Detect wrong password when extracting 7z archive

Aspose.ZIP Product Family
1

Hi,

I have a 7z archive with one file that is encrypted. When I extract the file using an incorrect password, the extraction completes without error. The extracted content is of course wrong as the password was wrong.

Is there a way that Aspose.Zip can tell that the password was incorrect, so I can stop processing at that point?

2

Hello @benarnold, it is strange you have not got InvalidDataException. What compression method uses that archive? You can also attach it here for us to review.

3

Hi Eugene,

Here is a small example that shows it. Hopefully you can show me what I’m doing wrong :slight_smile:

using Aspose.Zip.Saving;
using Aspose.Zip.SevenZip;
using System.Text;

var archive = new SevenZipArchive(new SevenZipEntrySettings(
    new SevenZipStoreCompressionSettings(),
    new SevenZipAESEncryptionSettings("PASSWORD")));

archive.CreateEntry("example.text", new MemoryStream(Encoding.UTF8.GetBytes("hello")));

var archiveStream = new MemoryStream();
archive.Save(archiveStream);
archiveStream.Position = 0;

var unarchive = new SevenZipArchive(archiveStream);

var unarchiveStream = new MemoryStream();
unarchive.Entries[0].Extract(unarchiveStream, "the-wrong-password");

Console.WriteLine(Encoding.UTF8.GetString(unarchiveStream.ToArray()));
4

Oh, you are using store (no compression) method. Lacking exception here is a bug. We opened a ticket ZIPNET-1017 for this. We’ll notify you when it fixed, most likely in March version.

5

Version 23.5 raises exception on extraction with wrong password.

6

Thanks Eugene, I’ll try it out

7

BTW, SevenZipArchive is IDisposable, so please wrap it with using statement.