CyberSecBulletin
CVE-2026-46070NVD status: Undergoing Analysis

Linux: Out-of-bounds Write

Published Updated By the CyberSecBulletin desk

CVE-2026-46070 is a high-severity out-of-bounds write 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 c96c6f01d84b5c67db1bf1cc8591c0b7146826fc, ef4851d8324fd978ca1ff9ec76a275438f887743, 28d3ff7109c66e99dc1b7cddacb5c760849620ef 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 c96c6f01d84b5c67db1bf1cc8591c0b7146826fc or ef4851d8324fd978ca1ff9ec76a275438f887743 or 28d3ff7109c66e99dc1b7cddacb5c760849620ef or 33698bd1b2db9764a29df7751533d33967ff5c98, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.10.258 or 5.15.209 or 6.1.175 or 6.6.140, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinuxb4c625c67362b3940f619c1a836b4e8329106658 up to, but not including, c96c6f01d84b5c67db1bf1cc8591c0b7146826fc; b4c625c67362b3940f619c1a836b4e8329106658 up to, but not including, ef4851d8324fd978ca1ff9ec76a275438f887743; b4c625c67362b3940f619c1a836b4e8329106658 up to, but not including, 28d3ff7109c66e99dc1b7cddacb5c760849620ef; b4c625c67362b3940f619c1a836b4e8329106658 up to, but not including, 33698bd1b2db9764a29df7751533d33967ff5c98; b4c625c67362b3940f619c1a836b4e8329106658 up to, but not including, c3a1cf78bd1bbb51b2cc5189b4743056553c1e0e; b4c625c67362b3940f619c1a836b4e8329106658 up to, but not including, 73ce72edd113374801045924d4417199963f73a3; b4c625c67362b3940f619c1a836b4e8329106658 up to, but not including, 406aa86394ead347c47428fb51b6359bdaa2257d; b4c625c67362b3940f619c1a836b4e8329106658 up to, but not including, b0cc3ae97e893bf54bbce447f4e9fd2e0b88bff9; and 1 more rangesc96c6f01d84b5c67db1bf1cc8591c0b7146826fc, ef4851d8324fd978ca1ff9ec76a275438f887743, 28d3ff7109c66e99dc1b7cddacb5c760849620ef, 33698bd1b2db9764a29df7751533d33967ff5c98, c3a1cf78bd1bbb51b2cc5189b4743056553c1e0e, 73ce72edd113374801045924d4417199963f73a3
SiemensSIMATIC S7-1500 TM MFP - GNU/Linux subsystemall versionsNot stated
LinuxLinux Kernel4.10 up to, but not including, 5.10.258; 5.11 up to, but not including, 5.15.209; 5.16 up to, but not including, 6.1.175; 6.2 up to, but not including, 6.6.140; 6.7 up to, but not including, 6.12.86; 6.13 up to, but not including, 6.18.27; 6.19 up to, but not including, 7.0.45.10.258, 5.15.209, 6.1.175, 6.6.140, 6.12.86, 6.18.27

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 CNA.

Official description

In the Linux kernel, the following vulnerability has been resolved: md/raid5: validate payload size before accessing journal metadata r5c_recovery_analyze_meta_block() and r5l_recovery_verify_data_checksum_for_mb() iterate over payloads in a journal metadata block using on-disk payload size fields without validating them against the remaining space in the metadata block. A corrupted journal contains payload sizes extending beyond the PAGE_SIZE boundary can cause out-of-bounds reads when accessing payload fields or computing offsets. Add bounds validation for each payload type to ensure the full payload fits within meta_size before processing.

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

References

Recent Out-of-bounds Write vulnerabilities

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