CVE-2026-64233usb: gadget: uvc: hold opts->lock across XU walks in uvc_function_bind
- 5.5MediumCVSS base score
- 0.11%Exploitation in 30 daysEPSS · top 98% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In the Linux kernel, the following vulnerability has been resolved: usb: gadget: uvc: hold opts->lock across XU walks in uvc_function_bind uvc_function_bind() walks &opts->extension_units twice without holding opts->lock: - directly, for the iExtension string-descriptor fixup loop; - indirectly, four times via uvc_copy_descriptors() (once per speed), where the helper iterates uvc->desc.extension_units (which aliases &opts->extension_units) to size and emit XU descriptors. The configfs side (uvcg_extension_make / uvcg_extension_drop, in drivers/usb/gadget/function/uvc_configfs.c) takes opts->lock around its list_add_tail / list_del operations. A privileged userspace process that holds the configfs subtree open and writes the gadget UDC name to bind the function while concurrently rmdir()'ing an extensions subdir can race uvcg_extension_drop() against the bind-time list walks and dereference a freed struct uvcg_extension. Hold opts->lock from the start of the XU string-descriptor fixup through the last uvc_copy_descriptors() call, releasing on the descriptor-error path via a new error_unlock label that drops the lock before falling through to the existing error label. This matches the locking discipline of the configfs callbacks and removes the only remaining unsynchronised reader of the XU list during bind. Reachability: only privileged processes that can mount configfs and write to gadget UDC files can trigger the race, so this is a correctness fix rather than a security boundary.
Timeline
ID reserved
By Linux
- 5 days later
· 5 days later
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Analyzed | 3.1 | Medium5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.11% · top 98% of all CVEs (14 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.5.
Affected products
- affected 0525210c9840229e42c6b68e886c72a75a67cf8e – < e15c414092b3c24610cc771e481a723b0f645eca
- affected 0525210c9840229e42c6b68e886c72a75a67cf8e – < 2c9e0905ef7e69f7b814cd709613f6b3b5b98805
- affected 0525210c9840229e42c6b68e886c72a75a67cf8e – < caec0145e5974e85fe5192fc6a6f5aa1a98f82a6
- affected 0525210c9840229e42c6b68e886c72a75a67cf8e – < 5f1b9cff88982e2a2053d8b1fd983f7ccb9f03cc
- affected 0525210c9840229e42c6b68e886c72a75a67cf8e – < 68aa70648b625fa684bc0b71bbfd905f4943ca20
- affected 6.3
- unaffected < 6.3
- unaffected 6.6.143 – ≤ 6.6.*
- unaffected 6.12.93 – ≤ 6.12.*
- unaffected 6.18.35 – ≤ 6.18.*
- unaffected 7.0.12 – ≤ 7.0.*
- unaffected 7.1 – ≤ *
References
References5
- https://git.kernel.org/stable/c/e15c414092b3c24610cc771e481a723b0f645eca (opens in a new tab)
- https://git.kernel.org/stable/c/2c9e0905ef7e69f7b814cd709613f6b3b5b98805 (opens in a new tab)
- https://git.kernel.org/stable/c/caec0145e5974e85fe5192fc6a6f5aa1a98f82a6 (opens in a new tab)
- https://git.kernel.org/stable/c/5f1b9cff88982e2a2053d8b1fd983f7ccb9f03cc (opens in a new tab)
- https://git.kernel.org/stable/c/68aa70648b625fa684bc0b71bbfd905f4943ca20 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-48642 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-64233)Record last updated .