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Fencer Vulns
no cvss —

CVE-2026-89739 json

usb: dwc3: gadget: Fix use-after-free in dwc3_gadget_free_endpoints due to race condition

published 2026-09-11 58 d ago modified 2026-10-21 19 d ago also EUVD-2026-76651

cvss
—
not scored
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 11%
public exploits
0
none known

Summary

In the Linux kernel, the following vulnerability has been resolved:

usb: dwc3: gadget: Fix use-after-free in dwc3_gadget_free_endpoints due to race condition

In dwc3_gadget_init_endpoint, &dep->nostream_work is bound with dwc3_nostream_work, and dwc3_gadget_endpoint_stream_event can queue this delayed work on system_percpu_wq when a DEPEVT_STREAM_NOSTREAM event is received.

If we remove the gadget, dwc3_gadget_free_endpoints makes cleanup and the memory allocated for dep with kzalloc() is released by kfree(dep), while the delayed work mentioned above may still be pending or running. The sequence of operations that may lead to a UAF bug is as follows:

CPU0 CPU1

| dwc3_thread_interrupt | dwc3_endpoint_interrupt | dwc3_gadget_endpoint_stream_event | queue_delayed_work(system_percpu_wq, | &dep->nostream_work) dwc3_gadget_free_endpoints | dwc3_free_trb_pool(dep) | list_del(&dep->endpoint.ep_list) | dwc3_debugfs_remove_endpoint_dir(dep) | kfree(dep) | // dep is freed | | dwc3_nostream_work | // use dep (use-after-free)

Fix it by canceling the delayed work before kfree(dep) in dwc3_gadget_free_endpoints.

Patch / fix

  • Linux Linux 6.7, 6.18.50, 7.2.4, 7.3
  • linux Debian 14 7.2.6-1

debian advisories DEBIAN-CVE-2026-89739

  • linux Ubuntu 26.04 LTS 7.0.0-42.42
  • linux-aws Ubuntu 26.04 LTS 7.0.0-1016.17
  • linux-gcp Ubuntu 26.04 LTS 7.0.0-1016.18
  • linux-ibm Ubuntu 26.04 LTS 7.0.0-1017.17
  • linux-riscv Ubuntu 26.04 LTS 7.0.0-42.42.1
  • linux-oracle Ubuntu 26.04 LTS 7.0.0-1015.16
  • linux-hwe-7.0 Ubuntu 24.04 LTS 7.0.0-42.42~24.04.1
  • linux-oem-7.0 Ubuntu 26.04 LTS 7.0.0-1017.17

ubuntu advisories UBUNTU-CVE-2026-89739

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • kernel-source Linux Micro 6.0 6.4.0-159998.55.1
  • kernel-default Linux Micro 6.0 6.4.0-159998.55.1
  • kernel-kvmsmall Linux Micro 6.0 6.4.0-159998.55.1
  • kernel-default-base Linux Micro 6.0 6.4.0-159998.55.1.159998.21.42
  • kernel-64kb SLE Module for Basesystem 15 SP7 6.4.0-150700.53.90.1
  • kernel-syms SLE Module for Development Tools 15 SP7 6.4.0-150700.53.90.1
  • kernel-azure SLE Module for Public Cloud 15 SP7 6.4.0-150700.53.90.1
  • kernel-source SLE Module for Development Tools 15 SP7, SLE Module for Basesystem 15 SP7 6.4.0-150700.53.90.1

suse advisories SUSE-SU-2026:24550-1SUSE-SU-2026:5091-1

  • kernel-source openSUSE Tumbleweed 7.2.7-1.1

opensuse advisories openSUSE-SU-2026:11880-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-89739 updated cvss 4.7

kernel: usb: dwc3: gadget: Fix use-after-free in dwc3_gadget_free_endpoints due to race condition

  • Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +82 more Red Hat Enterprise Linux 10 kernel Red Hat OpenShift Container Platform 4 openshift/ose-rhel-coreos-9
    affected: workaround, no fix available “Fix deferred”
  • Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 kernel-rt, kernel-rt-selftests-internal Red Hat OpenShift Container Platform 4 openshift/ose-rhel-coreos-8
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

0.21% chance of exploitation in the next 30 days, higher than 11% of all scored CVEs (FIRST EPSS, 2026-11-08).

Affected products

  • Linux Linux

Classification

Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.