CyberSecBulletin
CVE-2026-43078NVD status: Modified

Linux: Out-of-bounds Write

Published Updated By the CyberSecBulletin desk

CVE-2026-43078 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 fa48d3ea9cdbfb28c1fd6756c6c5cd01351aa51e, 2b781d1d4f933990318bcc5c68fb75a717379e42, f7826bc0b39928a4a22f6b815dd9940b22a63503 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 fa48d3ea9cdbfb28c1fd6756c6c5cd01351aa51e or 2b781d1d4f933990318bcc5c68fb75a717379e42 or f7826bc0b39928a4a22f6b815dd9940b22a63503 or 710a4ce5d7afd9fe082c75dec282ab4a11c0fe71, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.10.254 or 5.15.204 or 6.1.170 or 6.6.137, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinuxe870456d8e7c8d57c059ea479b5aadbb55ff4c3a up to, but not including, fa48d3ea9cdbfb28c1fd6756c6c5cd01351aa51e; e870456d8e7c8d57c059ea479b5aadbb55ff4c3a up to, but not including, 2b781d1d4f933990318bcc5c68fb75a717379e42; e870456d8e7c8d57c059ea479b5aadbb55ff4c3a up to, but not including, f7826bc0b39928a4a22f6b815dd9940b22a63503; e870456d8e7c8d57c059ea479b5aadbb55ff4c3a up to, but not including, 710a4ce5d7afd9fe082c75dec282ab4a11c0fe71; e870456d8e7c8d57c059ea479b5aadbb55ff4c3a up to, but not including, c8369a6d62f5abde9cbd4b62c45bf4b996be2468; e870456d8e7c8d57c059ea479b5aadbb55ff4c3a up to, but not including, dea5fcf085f977b6c2de1b2d4ec4767b6c840d1f; e870456d8e7c8d57c059ea479b5aadbb55ff4c3a up to, but not including, 9532501e0f1b200ea80baa0e33e0b06da10bb271; e870456d8e7c8d57c059ea479b5aadbb55ff4c3a up to, but not including, 31d00156e50ecad37f2cb6cbf04aaa9a260505ef; and 1 more rangesfa48d3ea9cdbfb28c1fd6756c6c5cd01351aa51e, 2b781d1d4f933990318bcc5c68fb75a717379e42, f7826bc0b39928a4a22f6b815dd9940b22a63503, 710a4ce5d7afd9fe082c75dec282ab4a11c0fe71, c8369a6d62f5abde9cbd4b62c45bf4b996be2468, dea5fcf085f977b6c2de1b2d4ec4767b6c840d1f
LinuxLinux Kernel4.14.1 up to, but not including, 5.10.254; 5.11 up to, but not including, 5.15.204; 5.16 up to, but not including, 6.1.170; 6.2 up to, but not including, 6.6.137; 6.7 up to, but not including, 6.12.85; 6.13 up to, but not including, 6.18.24; 6.19 up to, but not including, 6.19.14; 4.14; and 1 more ranges5.10.254, 5.15.204, 6.1.170, 6.6.137, 6.12.85, 6.18.24

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: crypto: af_alg - Fix page reassignment overflow in af_alg_pull_tsgl When page reassignment was added to af_alg_pull_tsgl the original loop wasn't updated so it may try to reassign one more page than necessary. Add the check to the reassignment so that this does not happen. Also update the comment which still refers to the obsolete offset argument.

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.