CVE-2026-43040: Linux vulnerability

CVE-2026-43040: net: ipv6: ndisc: fix ndisc_ra_useropt to initialize nduseropt_padX fields to zero to prevent an info-leak

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.

UnknownCVSS not scoredNot KEV-listedUpdatedOct 15, 2026, 01:18 UTC (UTC+00:00)

Potential ATT&CK relevance

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Vulnerability profileCVE Program record

Severity: Unknown
CVSS: Not scored
Known Exploited: No
Published: May 1, 2026, 14:15 UTC (UTC+00:00)

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

0CVSS vectors

3Timeline events

1ADP providers

12Source links

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
May 1, 2026, 14:12 UTC (UTC+00:00)
CVE publishedCVE Program
The CVE record was published.
May 1, 2026, 14:15 UTC (UTC+00:00)
CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
Oct 15, 2026, 01:18 UTC (UTC+00:00)

ADP provider summaries

Source materials

CVE List V5 sourceCVE List V5
https://git.kernel.org/stable/c/1da9023f6b071a38e5430ffbce4b70b2b1ac4f9cCVE reference, Linux
https://git.kernel.org/stable/c/2fe4d0ba690a69ad6ae9f7ab9bdc96e02610b648CVE reference, Linux
https://git.kernel.org/stable/c/11d7fe97421cfc81549940c20ed5ac9472d6db05CVE reference, Linux
https://git.kernel.org/stable/c/7f56d87e527bb5a13c3e8b0d5840cb6332822f6dCVE reference, Linux
https://git.kernel.org/stable/c/4f810c686fde509d1cdaa706322d9d2531f8f1a4CVE reference, Linux
https://git.kernel.org/stable/c/b485eef3d97b7aae55ce669b6de555ec81f3d21cCVE reference, Linux
https://git.kernel.org/stable/c/ef3645606e4a635d5062a492f22b7f490852ee67CVE reference, Linux
https://git.kernel.org/stable/c/ae05340ccaa9d347fe85415609e075545bec589fCVE reference, Linux
https://cert-portal.siemens.com/productcert/html/ssa-082556.htmlCVE reference, siemens-SADP
https://cert-portal.siemens.com/productcert/html/ssa-019113.htmlCVE reference, siemens-SADP
https://cert-portal.siemens.com/productcert/html/ssa-457936.htmlCVE reference, siemens-SADP

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus

LinuxLinux31910575a9de61e78065e93846e8e7a4894a18bf, 31910575a9de61e78065e93846e8e7a4894a18bf, 31910575a9de61e78065e93846e8e7a4894a18bf, 31910575a9de61e78065e93846e8e7a4894a18bf, 31910575a9de61e78065e93846e8e7a4894a18bf, 31910575a9de61e78065e93846e8e7a4894a18bf, 31910575a9de61e78065e93846e8e7a4894a18bf, 31910575a9de61e78065e93846e8e7a4894a18bfunaffected

LinuxLinux2.6.24, 0, 5.10.253, 5.15.203, 6.1.168, 6.6.134, 6.12.81, 6.18.22, 6.19.12, 7.0affected

Weakness

CWE details

No CWE listed

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