I have installed jdk-9.0.1osx-x64bin.dmg from Oracle's website. When I attempt to mount it, the checksum fails. I have entered defaults write com.apple.frameworks.diskimages skip-verify true into Terminal to mount the file, yet the software later fails to install. Sep 30, 2010 The DMG File I am getting a dialogue box with the warning: The following disk images could not be opened: ParallelsDesktop-parallels-enUS-6.0.90.dmg Invalid checksum Has anyone else got this? I have downloaded it from 2 separate locations. It would appear the.dmg file on the web site is corrupt. Is there another DMG file I can access?
We do not publish checksums of Malwarebytes for Mac on our website, for a couple reasons. First, checksums are a poor method of verifying the integrity of an app. If you suppose that a hacker has replaced the app on a developer’s website with a hacked copy, then the checksum could just as easily have been replaced.
Second, keeping checksums updated is a pain.
A code signature is a far better option. Code signatures can be validated independently, and are an important aspect of security on macOS. Both the Malwarebytes for Mac installer and the app are cryptographically signed.
Verifying the installer
To verify the installer for Malwarebytes 3.0 prior to installation, perform the following steps:
- Open the Malwarebytes-3.x.y.zzz.dmg file that you downloaded from our website.
- Open the Terminal app (found in the Utilities folder in the Applications folder)
- Execute the following command in the Terminal:
pkgutil --check-signature '/Volumes/Malwarebytes/Install Malwarebytes 3.pkg'
- Note: if the installer is in a different location, you can insert the path to the installer by dragging the .pkg file onto the Terminal window.
![Invalid Invalid](https://gwhiz.files.wordpress.com/2006/09/disk-utilityscreensnapz001.jpg?w=376)
If the output of this command says that the package is invalid, it has been tampered with and should not be installed.
In addition, if the output shows anything other than Malwarebytes Corporation (GVZRY6KDKR) as the first entry in the certificate chain, then the installer has been tampered with and re-signed by someone else, and should not be installed.
Verifying the application
To verify that the application itself has not been modified, the following steps will be required.
- Open System Preferences from the Apple menu, then click the Security & Privacy icon
- If 'Allow apps downloaded from' is set to 'App Store':
- Unlock the Security & Privacy settings by clicking the lock in the bottom left corner of the window
- Temporarily set 'Allow apps downloaded from' to 'App Store and identified developers
- Open the Terminal app (found in the Utilities folder in the Applications folder)
- Execute the following command in the Terminal:
codesign -dvvv /Applications/Malwarebytes.app
![Mac Invalid Checksum Dmg 1 Mac Invalid Checksum Dmg 1](http://www.betalogue.com/images/uploads/roxio/toast10-diskimage.png)
- Then execute the following command:
spctl --assess --verbose=4 /Applications/Malwarebytes.app
- Note: if the application is in a different location, you can insert the path to the app by dragging it onto the Terminal window.
- If you changed the 'Allow apps downloaded from' setting, you can change it back now
The output from the first command should indicate that the authority is Malwarebytes Corporation (GVZRY6KDKR). The second command will output the following if the application's signature is valid:
/Applications/Malwarebytes.app: accepted
source=Developer ID
If the application has been tampered with, it will instead display:
/Applications/Malwarebytes.app: invalid resource directory (directory or signature have been modified)
At the beginning of a disk image file is the sum of all the bits in that file. The program will then checksum to see if the sum is what is really in the image. If it is off, it reports 'invalid checksum'
If you downloaded it from a website, it likely was corrupted during download, and I would suggest trying to download it again. If you downloaded it from a peer to peer network, the file may be a fake.
You maybe able to skip the check sum at your own risk:
Checksums are there to protect you.
To enable skipping of the checksum verification to speed up mounting. So use the following (in Terminal):
*defaults write com.apple.frameworks.diskimages skip-verify true*
This will turn off disk image verification system-wide, regardless of what client has requested the mount (e.g. Finder or Safari or Disk Utility or DiskImageMounter.app).
Message was edited by: leroydouglas
If you downloaded it from a website, it likely was corrupted during download, and I would suggest trying to download it again. If you downloaded it from a peer to peer network, the file may be a fake.
You maybe able to skip the check sum at your own risk:
Checksums are there to protect you.
To enable skipping of the checksum verification to speed up mounting. So use the following (in Terminal):
*defaults write com.apple.frameworks.diskimages skip-verify true*
This will turn off disk image verification system-wide, regardless of what client has requested the mount (e.g. Finder or Safari or Disk Utility or DiskImageMounter.app).
Message was edited by: leroydouglas
Nov 9, 2010 1:56 PM