Medium 5.5Published Jul 25, 2026

CVE-2026-64327usb: gadget: f_fs: Initialize epfile->in early to fix endpoint direction checks

Updated under an hour ago (Oct 26, 2026, 5:50 PM ET)

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Exploited in the last 30 days

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_fs: Initialize epfile->in early to fix endpoint direction checks When parsing endpoint descriptors, ffs_data_got_descs() generates the eps_addrmap which contains the endpoint direction. However, epfile->in was previously only populated in ffs_func_eps_enable() which executes upon USB host connection. As a result, early userspace ioctls like FUNCTIONFS_DMABUF_ATTACH that run before the host connects would see epfile->in as 0, leading to incorrect DMA directions. By moving the initialization to ffs_epfiles_create(), epfile->in is accurate before userspace opens the endpoint files.

CVSS: 5.5 MEDIUM (v3.1, NVD)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): Not given
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Linux
NVD analysis: Analyzed
Record last updated: Aug 17, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Linux Linux linux:linux (from the name)	from 7b07a2a7ca02a20124b552be96c5a56910795488 before 82cf1142e5ccf2b6d6d22ef713aaf3e5f2b5716b; from 7b07a2a7ca02a20124b552be96c5a56910795488 before 9e04055ab5fc0470a0031ee6934739f9aa8f34a5; from 7b07a2a7ca02a20124b552be96c5a56910795488 before f99f32ea9aa976afcbec20647ed33b50a52002c1; from 7b07a2a7ca02a20124b552be96c5a56910795488 before 82cfd4739011bdc7e87b5d585703427e89ddfaa5	CNA record
linux linux_kernel linux:linux_kernel	from 6.9 before 6.12.96; from 6.13 before 6.18.39; from 6.19 before 7.1.4; 7.2; 7.2	NVD

References

References

https://git.kernel.org/stable/c/82cf1142e5ccf2b6d6d22ef713aaf3e5f2b5716b	patch
https://git.kernel.org/stable/c/9e04055ab5fc0470a0031ee6934739f9aa8f34a5	patch
https://git.kernel.org/stable/c/f99f32ea9aa976afcbec20647ed33b50a52002c1	patch
https://git.kernel.org/stable/c/82cfd4739011bdc7e87b5d585703427e89ddfaa5	patch

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.