CyberSecBulletin
CVE-2026-64126NVD status: Modified

Linux: Out-of-bounds Read

Published Updated By the CyberSecBulletin desk

CVE-2026-64126 is a high-severity out-of-bounds read vulnerability in Linux, with a CVSS 3.1 base score of 7.3 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 0d5104390b445e7bd664ad583837e4c04d892c9d, 14b01b9cba04e6ce82825f68fc4c4322fa4ffa43, a143ce77a5292f2c9285137433d879ce71d190a7 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 0.14% 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 0d5104390b445e7bd664ad583837e4c04d892c9d or 14b01b9cba04e6ce82825f68fc4c4322fa4ffa43 or a143ce77a5292f2c9285137433d879ce71d190a7 or a6c75a3fad226ccbd8ef9110dee87c92c299f2ab, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.15.210 or 6.1.175 or 6.6.142 or 6.12.92, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux12410572833a283ce92fcf9679ca8a2f372097ee up to, but not including, 0d5104390b445e7bd664ad583837e4c04d892c9d; 12410572833a283ce92fcf9679ca8a2f372097ee up to, but not including, 14b01b9cba04e6ce82825f68fc4c4322fa4ffa43; 12410572833a283ce92fcf9679ca8a2f372097ee up to, but not including, a143ce77a5292f2c9285137433d879ce71d190a7; 12410572833a283ce92fcf9679ca8a2f372097ee up to, but not including, a6c75a3fad226ccbd8ef9110dee87c92c299f2ab; 12410572833a283ce92fcf9679ca8a2f372097ee up to, but not including, f1febe93ef075314615f970a87681d9ab86691d1; 12410572833a283ce92fcf9679ca8a2f372097ee up to, but not including, 0bc1a5a69f541859293d79db72bd7854ac48df51; 12410572833a283ce92fcf9679ca8a2f372097ee up to, but not including, d3f7d17960ed50df3a6709c5158caff989c8c905; 5.110d5104390b445e7bd664ad583837e4c04d892c9d, 14b01b9cba04e6ce82825f68fc4c4322fa4ffa43, a143ce77a5292f2c9285137433d879ce71d190a7, a6c75a3fad226ccbd8ef9110dee87c92c299f2ab, f1febe93ef075314615f970a87681d9ab86691d1, 0bc1a5a69f541859293d79db72bd7854ac48df51
LinuxLinux Kernel5.11 up to, but not including, 5.15.210; 5.16 up to, but not including, 6.1.175; 6.2 up to, but not including, 6.6.142; 6.7 up to, but not including, 6.12.92; 6.13 up to, but not including, 6.18.34; 6.19 up to, but not including, 7.0.11; 7.15.15.210, 6.1.175, 6.6.142, 6.12.92, 6.18.34, 7.0.11

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
HighData or code can be modified at will.
Availability
LowPerformance or availability is reduced.

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

Official description

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: MGMT: validate Add Extended Advertising Data length MGMT_OP_ADD_EXT_ADV_DATA is registered as a variable-length command, with MGMT_ADD_EXT_ADV_DATA_SIZE as the fixed header size. The handler then uses cp->adv_data_len and cp->scan_rsp_len to validate and copy cp->data, but it never checks that those bytes are part of the mgmt command payload. A short command can therefore make add_ext_adv_data() pass an out-of-bounds pointer into tlv_data_is_valid(). If the bytes beyond the command buffer are addressable, they can also be copied into the advertising instance as scan response data, where the caller can read them back via MGMT_OP_GET_ADV_INSTANCE. The trigger requires CAP_NET_ADMIN in the initial user namespace; KASAN reports an 8-byte slab-out-of-bounds read. Reject commands whose length does not match the fixed header plus both advertising data lengths before parsing cp->data.

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: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Out-of-bounds Read vulnerabilities

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