CVE-2026-89739
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.
Affected versions
Linux kernel versions
6.14
and later are affected. Fixed in
6.18.50,
7.2.4,
7.3-rc1
and their respective stable series.
References
4 totalFrequently asked questions
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What is CVE-2026-89739?
CVE-2026-89739 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 6.14 onward and has been patched in 6.18.50, 7.2.4 and 7.3-rc1. CVE-2026-89739 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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Is there a patch available for CVE-2026-89739?
Yes. CVE-2026-89739 has been patched. Fixed versions include 6.18.50, 7.2.4 and 7.3-rc1. If you are running Linux kernel 6.14 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-89739 actively exploited?
No. CVE-2026-89739 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.