CyberSecBulletin
CVE-2026-64276NVD status: Modified

Linux: Out-of-bounds Write

Published Updated By the CyberSecBulletin desk

CVE-2026-64276 is a high-severity out-of-bounds write vulnerability in Linux, with a CVSS 3.1 base score of 7.8 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 8c6d18d61bb6fe0e6edf848413391c590552e8a9, d162a1ead7de404d8b41a093c83ed0db6487cded, f0be9eba946e9200b43265e0a748d38bd0a56954 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 0.17% 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 8c6d18d61bb6fe0e6edf848413391c590552e8a9 or d162a1ead7de404d8b41a093c83ed0db6487cded or f0be9eba946e9200b43265e0a748d38bd0a56954 or 26c895928d7118436a24f564587cb4aefc40cdd8, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.10.261 or 5.15.212 or 6.1.178 or 6.6.145, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux3e64fcbdbd10e46dede502d507dbcc104837cd59 up to, but not including, 8c6d18d61bb6fe0e6edf848413391c590552e8a9; 3e64fcbdbd10e46dede502d507dbcc104837cd59 up to, but not including, d162a1ead7de404d8b41a093c83ed0db6487cded; 3e64fcbdbd10e46dede502d507dbcc104837cd59 up to, but not including, f0be9eba946e9200b43265e0a748d38bd0a56954; 3e64fcbdbd10e46dede502d507dbcc104837cd59 up to, but not including, 26c895928d7118436a24f564587cb4aefc40cdd8; 3e64fcbdbd10e46dede502d507dbcc104837cd59 up to, but not including, 4e3689c26854356f41fbaa1eafa382e58ac79e00; 3e64fcbdbd10e46dede502d507dbcc104837cd59 up to, but not including, e849c6f51e6877104c765da084e001ec37c8e119; 3e64fcbdbd10e46dede502d507dbcc104837cd59 up to, but not including, bfe622efecd4ff0a792d0ecd1a8dce535a902f50; 3e64fcbdbd10e46dede502d507dbcc104837cd59 up to, but not including, d577e46785d45484b2ab7e7309c49b18764bf56c; and 1 more ranges8c6d18d61bb6fe0e6edf848413391c590552e8a9, d162a1ead7de404d8b41a093c83ed0db6487cded, f0be9eba946e9200b43265e0a748d38bd0a56954, 26c895928d7118436a24f564587cb4aefc40cdd8, 4e3689c26854356f41fbaa1eafa382e58ac79e00, e849c6f51e6877104c765da084e001ec37c8e119
LinuxLinux Kernel4.14.1 up to, but not including, 5.10.261; 5.11 up to, but not including, 5.15.212; 5.16 up to, but not including, 6.1.178; 6.2 up to, but not including, 6.6.145; 6.7 up to, but not including, 6.12.96; 6.13 up to, but not including, 6.18.39; 6.19 up to, but not including, 7.1.4; 4.145.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.96, 6.18.39

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
HighThe component can be taken down completely.

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

Official description

In the Linux kernel, the following vulnerability has been resolved: Input: synaptics-rmi4 - bound the F30 keymap to the GPIO/LED count rmi_f30_map_gpios() allocates gpioled_key_map with min(gpioled_count, TRACKSTICK_RANGE_END) == at most 6 entries, but rmi_f30_attention() iterates the full f30->gpioled_count (device query register, range 0..31) and dereferences gpioled_key_map[i], and input->keycodemax is set to the full gpioled_count while input->keycode points at the 6-entry allocation. A device that reports gpioled_count > 6 with GPIO support enabled therefore causes an out-of-bounds read on the attention interrupt and out-of-bounds read/write through the EVIOCGKEYCODE/EVIOCSKEYCODE ioctls, which bound the index only against keycodemax. This is the same defect as the F3A handler, which was copied from F30. Size the keymap for the full gpioled_count; the mapping loop still assigns only the first min(gpioled_count, TRACKSTICK_RANGE_END) entries.

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

The underlying weakness: Out-of-bounds Write

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

How developers prevent this class of flaw

  • Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, many languages that perform their own memory management, such as Java and Perl, are not subject to buffer overflows. Other languages, such as Ada and C#, typically provide overflow protection, but the protection can be disabled by the programmer. Be wary that a language's interface to native code may still be subject to overflows, even if the language itself is theoretically safe.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Examples include the Safe C String Library (SafeStr) by Messier and Viega, and the Strsafe.h library from Microsoft. These libraries provide safer versions of overflow-prone string-handling functions.
  • Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking. D3-SFCV (Stack Frame Canary Validation) from D3FEND discusses canary-based detection in detail.

More Out-of-bounds Write vulnerabilities (CWE-787)

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 Write vulnerabilities

Spotted an error? Tell us.