CVE-2026-31651

Local kernel crash via premature reference release

Published Apr 24, 2026 · Updated Apr 24, 2026

NULL-pointer dereference in the vub300 MMC driver in Linux Kernel allows local users to crash the kernel during controller disconnect. In vub300_disconnect(), the driver drops its final reference before mmc_remove_host() deregisters the controller, allowing driver data to be freed while removal still uses it. Exploitation requires local access to disconnect a bound VUB300 USB-to-SD/SDIO/MMC controller; the documented impact is a kernel crash rather than data disclosure or modification.

CVSS severity5.5
Medium
EPSS probability0.12%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

NULL-pointer dereference in the vub300 MMC driver in Linux Kernel allows local users to crash the kernel during controller disconnect. In vub300_disconnect(), the driver drops its final reference before mmc_remove_host() deregisters the controller, allowing driver data to be freed while removal still uses it. Exploitation requires local access to disconnect a bound VUB300 USB-to-SD/SDIO/MMC controller; the documented impact is a kernel crash rather than data disclosure or modification.

The record

CVE
CVE-2026-31651
Published
Apr 24, 2026
Updated
Apr 24, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-476, T1499
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 24, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 24, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=3.0
  2. Affected versionversion=88095e7b473a3d9ec3b9c60429576e9cbd327c89 <517b58e1d067115f80d198feee10192da4c424d0
  3. Affected versionversion=88095e7b473a3d9ec3b9c60429576e9cbd327c89 <53f2642d77ab5f1f303388bff5500363c6cf962c
  4. Affected versionversion=88095e7b473a3d9ec3b9c60429576e9cbd327c89 <6446516e626ce7c44bdadbcbb3d7677a2c52ce93
  5. Affected versionversion=88095e7b473a3d9ec3b9c60429576e9cbd327c89 <6468cab1173f44f7a4b7a05ce8abfdfd1ce1557a
  6. Affected versionversion=88095e7b473a3d9ec3b9c60429576e9cbd327c89 <8d09e75759cb2afc0732acfb5a14a93c03805a61
  7. Affected versionversion=88095e7b473a3d9ec3b9c60429576e9cbd327c89 <ba3b9429de94958dc0060d9816a915dd75c34919
  8. Affected versionversion=88095e7b473a3d9ec3b9c60429576e9cbd327c89 <c83a282615d8f7ba28cebddd54600b419d562d82
  9. Affected versionversion=88095e7b473a3d9ec3b9c60429576e9cbd327c89 <dff34ef879c5e73298443956a8b391311ba78d57

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=3.0; version=88095e7b473a3d9ec3b9c60429576e9cbd327c89 <517b58e1d067115f80d198feee10192da4c424d0; version=88095e7b473a3d9ec3b9c60429576e9cbd327c89 <53f2642d77ab5f1f303388bff5500363c6cf962c; version=88095e7b473a3d9ec3b9c60429576e9cbd327c89 <6446516e626ce7c44bdadbcbb3d7677a2c52ce93; version=88095e7b473a3d9ec3b9c60429576e9cbd327c89 <6468cab1173f44f7a4b7a05ce8abfdfd1ce1557a; version=88095e7b473a3d9ec3b9c60429576e9cbd327c89 <8d09e75759cb2afc0732acfb5a14a93c03805a61; version=88095e7b473a3d9ec3b9c60429576e9cbd327c89 <ba3b9429de94958dc0060d9816a915dd75c34919; version=88095e7b473a3d9ec3b9c60429576e9cbd327c89 <c83a282615d8f7ba28cebddd54600b419d562d82; version=88095e7b473a3d9ec3b9c60429576e9cbd327c89 <dff34ef879c5e73298443956a8b391311ba78d57

Published CVSS scores

5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-476NULL Pointer Dereference
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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