CVE-2026-89735: Linux kernel · usb: gadget: midi2: remove default configfs groups on teardown
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 28 Oct 2026, 01:01 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
Exploitation evidence
Disclosed: evidence found.
CVE published 11 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
In the Linux kernel, the following vulnerability has been resolved: usb: gadget: midi2: remove default configfs groups on teardown f_midi2_alloc_inst() creates default configfs child groups for the default endpoint and default block using configfs_add_default_group(), setting their internal refcount to 1. However, during function teardown in f_midi2_free_inst() or EP cleanup in f_midi2_ep_opts_release(), configfs_remove_default_groups() is never called, therefore never dropping the refcount and leaking struct f_midi2_ep_opts and f_midi2_block_opts. Add the missing configfs_remove_default_groups() in the afformentioned functions to free the structs properly.
References
- ubuntu.com/security/CVE-2026-89735 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-89735 (opens in a new tab)
- git.kernel.org/linus/0f6bffb5008f0cba9cad5ded2caccc64466a6e54 (opens in a new tab)
- git.kernel.org/stable/c/0f6bffb5008f0cba9cad5ded2caccc64466a6e54 (opens in a new tab)
- git.kernel.org/stable/c/4beda67ee72e0c8df5b49951dd8b96f6adb25e02 (opens in a new tab)
- git.kernel.org/stable/c/9ea5dfb2bfef4f8a7e704d1921d8a790cb7fb700 (opens in a new tab)
- git.kernel.org/stable/c/a15c2acd3083461f91725760e59dff88b33c28f6 (opens in a new tab)