Use After Free in Linux
CVE-2026-64348
In the Linux kernel, the following vulnerability has been resolved: usb: free iso schedules on failed submit EHCI and FOTG210 isochronous submits build an ehci_iso_sched before linking the URB to the endpoint queue, and keep the staged schedule in urb->hcpriv until iso_stream_schedule() and the link helpers consume it. If the controller is no longer accessible, or usb_hcd_link_urb_to_ep() fails, submit jumps to done_not_linked before that handoff happens and leaks the staged schedule still attached to urb->hcpriv. Free the staged schedule from done_not_linked when submit fails before the URB is linked and clear urb->hcpriv after the free. The bug was first flagged by an experimental analysis tool we are developing for kernel memory-management bugs while analyzing v6.13-rc1. The tool is still under development and is not yet publicly available. Manual inspection confirms that the bug is still present in v7.1.1. An x86_64 allyesconfig build showed no new warnings. As we do not have an EHCI host controller with a USB isochronous device to test with, no runtime testing was able to be performed.
Vulnerability class: Use-After-Free
EPSS: 0.001 (2.9th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Linux — versions 6.6.145, 7.2, 6.12.96
- Linux Linux_kernel — versions 2.6.15, 7.2
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-64348?
- CVE-2026-64348 is a high-severity vulnerability in Linux, classified under Use After Free. CVSS score: 7.8/10. Published 2026-07-25.
- How severe is CVE-2026-64348?
- High severity. CVSS v3 base score is 7.8 out of 10.