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CVE-2026-46140NVD status: Undergoing Analysis

Linux: Out-of-bounds Read

Published Updated By the CyberSecBulletin desk

CVE-2026-46140 is a high-severity out-of-bounds read vulnerability in Linux, with a CVSS 3.1 base score of 7.1 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions 36c85f7029484d5ede769f8873d16e9c8e35533c, c411cf1bfde951cfa821809cf4020ba177f76e0c, 624fb79dadc1b65757986a9d0fdde5c0cf3fe179 as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.13% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Linux to 36c85f7029484d5ede769f8873d16e9c8e35533c or c411cf1bfde951cfa821809cf4020ba177f76e0c or 624fb79dadc1b65757986a9d0fdde5c0cf3fe179 or 70d37a8b9229e394cc17ddad47e90b81d80fcd09, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 6.7 or 6.12.88 or 6.18.30 or 7.0.7, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinuxf0457842215438786e2e205ad06a4fbb8ab63cd0 up to, but not including, 36c85f7029484d5ede769f8873d16e9c8e35533c; d019930b0049fc2648a6b279893d8ad330596e81 up to, but not including, c411cf1bfde951cfa821809cf4020ba177f76e0c; d019930b0049fc2648a6b279893d8ad330596e81 up to, but not including, 624fb79dadc1b65757986a9d0fdde5c0cf3fe179; d019930b0049fc2648a6b279893d8ad330596e81 up to, but not including, 70d37a8b9229e394cc17ddad47e90b81d80fcd09; d019930b0049fc2648a6b279893d8ad330596e81 up to, but not including, 634a4408c0615c523cf7531790f4f14a422b9206; 6.6.142 up to, but not including, 6.6.144; 6.1136c85f7029484d5ede769f8873d16e9c8e35533c, c411cf1bfde951cfa821809cf4020ba177f76e0c, 624fb79dadc1b65757986a9d0fdde5c0cf3fe179, 70d37a8b9229e394cc17ddad47e90b81d80fcd09, 634a4408c0615c523cf7531790f4f14a422b9206, 6.6.144
LinuxLinux Kernel6.6.142 up to, but not including, 6.7; 6.11 up to, but not including, 6.12.88; 6.13 up to, but not including, 6.18.30; 6.19 up to, but not including, 7.0.7; 7.16.7, 6.12.88, 6.18.30, 7.0.7

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H. Scored by NVD.

Official description

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btmtk: validate WMT event SKB length before struct access btmtk_usb_hci_wmt_sync() casts the WMT event response SKB data to struct btmtk_hci_wmt_evt (7 bytes) and struct btmtk_hci_wmt_evt_funcc (9 bytes) without first checking that the SKB contains enough data. A short firmware response causes out-of-bounds reads from SKB tailroom. Use skb_pull_data() to validate and advance past the base WMT event header. For the FUNC_CTRL case, pull the additional status field bytes before accessing them.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Out-of-bounds Read

The product reads data past the end, or before the beginning, of the intended buffer.

How developers prevent this class of flaw

  • Use a language that provides appropriate memory abstractions.

More Out-of-bounds Read vulnerabilities (CWE-125)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Out-of-bounds Read vulnerabilities

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