CVE-2026-43040
net: ipv6: ndisc: fix ndisc_ra_useropt to initialize nduseropt_padX fields to zero to prevent an info-leak
Description
In the Linux kernel, the following vulnerability has been resolved: net: ipv6: ndisc: fix ndisc_ra_useropt to initialize nduseropt_padX fields to zero to prevent an info-leak When processing Router Advertisements with user options the kernel builds an RTM_NEWNDUSEROPT netlink message. The nduseroptmsg struct has three padding fields that are never zeroed and can leak kernel data The fix is simple, just zeroes the padding fields.
INFO
Published Date :
May 1, 2026, 3:16 p.m.
Last Modified :
May 8, 2026, 6:53 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Apply the kernel patch that zeroes padding fields.
- Update the Linux kernel to a fixed version.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-43040.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-43040 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-43040
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-43040 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-43040 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
May. 08, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H Added CWE CWE-909 Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.11 up to (excluding) 5.15.203 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.13 up to (excluding) 6.18.22 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.16 up to (excluding) 6.1.168 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.19 up to (excluding) 6.19.12 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.7 up to (excluding) 6.12.81 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.2 up to (excluding) 6.6.134 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 2.6.24 up to (excluding) 5.10.253 Added Reference Type kernel.org: https://git.kernel.org/stable/c/11d7fe97421cfc81549940c20ed5ac9472d6db05 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/1da9023f6b071a38e5430ffbce4b70b2b1ac4f9c Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/2fe4d0ba690a69ad6ae9f7ab9bdc96e02610b648 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/4f810c686fde509d1cdaa706322d9d2531f8f1a4 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/7f56d87e527bb5a13c3e8b0d5840cb6332822f6d Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/ae05340ccaa9d347fe85415609e075545bec589f Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/b485eef3d97b7aae55ce669b6de555ec81f3d21c Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/ef3645606e4a635d5062a492f22b7f490852ee67 Types: Patch -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
May. 01, 2026
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: net: ipv6: ndisc: fix ndisc_ra_useropt to initialize nduseropt_padX fields to zero to prevent an info-leak When processing Router Advertisements with user options the kernel builds an RTM_NEWNDUSEROPT netlink message. The nduseroptmsg struct has three padding fields that are never zeroed and can leak kernel data The fix is simple, just zeroes the padding fields. Added Reference https://git.kernel.org/stable/c/11d7fe97421cfc81549940c20ed5ac9472d6db05 Added Reference https://git.kernel.org/stable/c/1da9023f6b071a38e5430ffbce4b70b2b1ac4f9c Added Reference https://git.kernel.org/stable/c/2fe4d0ba690a69ad6ae9f7ab9bdc96e02610b648 Added Reference https://git.kernel.org/stable/c/4f810c686fde509d1cdaa706322d9d2531f8f1a4 Added Reference https://git.kernel.org/stable/c/7f56d87e527bb5a13c3e8b0d5840cb6332822f6d Added Reference https://git.kernel.org/stable/c/ae05340ccaa9d347fe85415609e075545bec589f Added Reference https://git.kernel.org/stable/c/b485eef3d97b7aae55ce669b6de555ec81f3d21c Added Reference https://git.kernel.org/stable/c/ef3645606e4a635d5062a492f22b7f490852ee67