CyberSecBulletin
CVE-2026-43279NVD status: Modified

Linux: Out-of-bounds Write

Published Updated By the CyberSecBulletin desk

CVE-2026-43279 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 fa01973bb79d70c4736b6a4b2de99fbb2cbc8d1f, 780dc57794a217b49994fa1d0b42465fb10a00aa, 8995fc0e00b3fee9bf7ecb3d836b635b730c1049 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 0.12% 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 fa01973bb79d70c4736b6a4b2de99fbb2cbc8d1f or 780dc57794a217b49994fa1d0b42465fb10a00aa or 8995fc0e00b3fee9bf7ecb3d836b635b730c1049 or fc9e5af60dc199051dc202ae78e1fe76a9977a5e, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.15.202 or 6.1.165 or 6.6.128 or 6.12.75, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinuxc75a8a7ae565d7cd9baa87a504ba9162e355b4b0 up to, but not including, fa01973bb79d70c4736b6a4b2de99fbb2cbc8d1f; c75a8a7ae565d7cd9baa87a504ba9162e355b4b0 up to, but not including, 780dc57794a217b49994fa1d0b42465fb10a00aa; c75a8a7ae565d7cd9baa87a504ba9162e355b4b0 up to, but not including, 8995fc0e00b3fee9bf7ecb3d836b635b730c1049; c75a8a7ae565d7cd9baa87a504ba9162e355b4b0 up to, but not including, fc9e5af60dc199051dc202ae78e1fe76a9977a5e; c75a8a7ae565d7cd9baa87a504ba9162e355b4b0 up to, but not including, 6af16f1b8649df4c00d6ced924bdd8b72c885b6a; c75a8a7ae565d7cd9baa87a504ba9162e355b4b0 up to, but not including, ccaf9296763be4f76b59e2cac377006016c34435; c75a8a7ae565d7cd9baa87a504ba9162e355b4b0 up to, but not including, fba2105a157fffcf19825e4eea498346738c9948; 3.5fa01973bb79d70c4736b6a4b2de99fbb2cbc8d1f, 780dc57794a217b49994fa1d0b42465fb10a00aa, 8995fc0e00b3fee9bf7ecb3d836b635b730c1049, fc9e5af60dc199051dc202ae78e1fe76a9977a5e, 6af16f1b8649df4c00d6ced924bdd8b72c885b6a, ccaf9296763be4f76b59e2cac377006016c34435
LinuxLinux Kernel3.5 up to, but not including, 5.15.202; 5.16 up to, but not including, 6.1.165; 6.2 up to, but not including, 6.6.128; 6.7 up to, but not including, 6.12.75; 6.13 up to, but not including, 6.18.16; 6.19 up to, but not including, 6.19.65.15.202, 6.1.165, 6.6.128, 6.12.75, 6.18.16, 6.19.6

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: ALSA: usb-audio: Add sanity check for OOB writes at silencing At silencing the playback URB packets in the implicit fb mode before the actual playback, we blindly assume that the received packets fit with the buffer size. But when the setup in the capture stream differs from the playback stream (e.g. due to the USB core limitation of max packet size), such an inconsistency may lead to OOB writes to the buffer, resulting in a crash. For addressing it, add a sanity check of the transfer buffer size at prepare_silent_urb(), and stop the data copy if the received data overflows. Also, report back the transfer error properly from there, too. Note that this doesn't fix the root cause of the playback error itself, but this merely covers the kernel Oops.

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.