Vulnerability · CVE-2026-43040
ZDI-26-682: Linux Kernel IPv6 Neighbour Discovery Uninitialized Memory Information Disclosure Vulnerability
Published May 1, 2026 · catalog updated Oct 15, 2026 · linux kernel
Check if you run it
No confirmed exploitation is on record for CVE-2026-43040. EPSS is 0.17%. Act only if a listed version of linux kernel is installed.
Gaps on this record
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- Severity
- High7.1
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.17%
- Remediation
- Advisory link
- Affected products
- cpe linux/linux kernel
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.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- cpe linux/linux kernel7.0
How to fix CVE-2026-43040
Recommended remediation
A patch or advisory reference is linked. Open the original publisher for availability by product version.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2026-43040. EPSS is 0.17%. Act only if a listed version of linux kernel is installed.
Which versions are affected?
Compare what you have installed with linux/linux kernel 7.0. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
CWE-909. EPSS 0.17%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
Timeline
Detection, updates, and resolution for this record.
Sep 14, 2026 · Catalog
Detected
This vulnerability allows local attackers to disclose sensitive information on affected installations of Linux Kernel. An attacker must first obtain the ability to execute high-privileged code on the target system in order to exploit this vulnerability. The ZDI has assigned a CVSS rating of 6.0. The following CVEs are assigned: CVE-2026-43040.
Oct 15, 2026 · NIST NVD
Updated
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,
Sources
- CVE.orgVulnerability recordCVE-2026-43040
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-43040
30-day exploitation probability 0.2%
first.org - NIST NVDVulnerability recordCVE-2026-43040
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 m
nvd.nist.gov - Zero Day InitiativeCoordinated disclosureZDI-26-682
This vulnerability allows local attackers to disclose sensitive information on affected installations of Linux Kernel. An attacker must first obtain the ability to execute high-privileged code on the target system in order to exploit this vulnerability. The ZDI has assigned a CVSS rating of 6.0. The following CVEs are assigned: CVE-2026-43040.
zerodayinitiative.com
References
Freshness
Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.