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Mumble 1.5.857

Posted on October 11, 2025 by Hartmnt

Today we release the second patch release in the Mumble 1.5.x series. This release includes fixes for undesired ACL behavior. If you are a server administrator, please continue reading the detailed explanation.

You can download the new version from our Downloads page or the GitHub release page or from within your Windows client or software package management system.

Changes to some ACL behavior

Attention Server Administrators:

We have fixed a few ACL-related behaviors that we have determined to be bugs. This is why we are including them in this patch-release. If you have ACLs configured which were relying on that undesired behavior, you want to make sure to fix your ACL configuration when updating your server to this release. We assume the number of impacted servers will be minimal and adapting the ACLs in case your server is affected will be reasonably easy.

  • Previously, both the Traverse and Write ACLs would be evaluated without taking the “in this channel” and “in sub-channels” context options into account. This is now fixed. You can now deny Traverse for sub-channels, while the channel you are defining the ACL in is still traversable. (#3579)
  • Previously, in addition to normal ACL inheritance rules, the Write ACL would always be inherited from the parent channel. For consistency, this was removed. To prevent “ungovernable” channels, users who are granted Write on the root channel, will be able to Write in any channel of the server, no matter what these sub-channels configure. (#6512)
  • Previously, the Register ACL was used to determine, if a client was able to see extended user information including user IP address and user-agent. This was changed to now require the Ban ACL. (#6697)
  • Due to the client being able to uncheck both context option checkboxes in the ACL editor, admins could create “dangling” ACLs that were present, but had no effect. Starting with this release, clients will not be able to create these “dangling” ACLs. Existing “dangling” ACLs will not be affected by this unless they are modfied. (#6512)

Changelog

This is the full changelog for this release (changes relative to the Mumble 1.5.735 release).

Client

  • Changed: Client-side max image width and height for better legibility (#6825)
  • Fixed: Bug with default values for talking UI options (#6728)
  • Fixed: Enable “Paste” action, if there is an image in clipboard (#6790)
  • Fixed: Infinite loop and log spam on ALSA input device disconnection (#6702)
  • Fixed: Limit size of images pasted in RichTextEditor (#6790)
  • Fixed: Memory leaks due to BIO_NOCLOSE (#6604)
  • Fixed: Message size limit bypass (#6875)
  • Fixed: Missing theme changes on macOS (#6925)
  • Fixed: Network packets of exactly max size are rejected (#6924)
  • Fixed: Prevent local muted users from triggering attenuation (#6747)
  • Fixed: Prevent unchecking both ACL context checkboxes (#6512)
  • Fixed: Rare crash when using PipeWire (#6852)
  • Fixed: Remove “Write” ACL parent channel inheritance (#6512)
  • Fixed: Restart audio system when a Windows audio device we use reappears (#6777)
  • Fixed: Shortcut data not being saved (#6832)
  • Fixed: Specify version when loading/saving MainWindow state (#6584)
  • Fixed: Text-To-Speech volume on macOS (#6896)
  • Fixed: Update chat bar, if selected channel changes name (#6748)
  • Fixed: Unlink active plugin before unloading (#6602)
  • Fixed: Volume adjustment slider keyboard inputs (#6841)

Server

  • Changed: Extended user stats now requires “Ban” ACL (#6700)
  • Fixed: ACL parsing of “Traverse” and “Write” ACL (#6512)
  • Fixed: Missing permission check on msgQueryUsers (#6916)
  • Fixed: Network packets of exactly max size are rejected (#6924)
  • Fixed: Prevent server startup when providing empty certificate files
  • Fixed: Remove “Write” ACL parent channel inheritance (#6512)

Windows Installer

  • Added: Bundle C++ redistributables on Windows (#6789) Many thanks to @sqwishy!

Known issues

  • macOS binaries not being signed/notarized (overlay installer not signed) (#4263)
  • Overlay blocked by BattleEye (Whitelisting request has been ignored)
  • Overlay blocked by CS:GO Trusted Mode