CVE-2026-43040 (GCVE-0-2026-43040)

Vulnerability from cvelistv5 – Published: 2026-05-01 14:15 – Updated: 2026-05-11 22:16
VLAI
Title
net: ipv6: ndisc: fix ndisc_ra_useropt to initialize nduseropt_padX fields to zero to prevent an info-leak
Summary
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.
Severity
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 31910575a9de61e78065e93846e8e7a4894a18bf , < 1da9023f6b071a38e5430ffbce4b70b2b1ac4f9c (git)
Affected: 31910575a9de61e78065e93846e8e7a4894a18bf , < 2fe4d0ba690a69ad6ae9f7ab9bdc96e02610b648 (git)
Affected: 31910575a9de61e78065e93846e8e7a4894a18bf , < 11d7fe97421cfc81549940c20ed5ac9472d6db05 (git)
Affected: 31910575a9de61e78065e93846e8e7a4894a18bf , < 7f56d87e527bb5a13c3e8b0d5840cb6332822f6d (git)
Affected: 31910575a9de61e78065e93846e8e7a4894a18bf , < 4f810c686fde509d1cdaa706322d9d2531f8f1a4 (git)
Affected: 31910575a9de61e78065e93846e8e7a4894a18bf , < b485eef3d97b7aae55ce669b6de555ec81f3d21c (git)
Affected: 31910575a9de61e78065e93846e8e7a4894a18bf , < ef3645606e4a635d5062a492f22b7f490852ee67 (git)
Affected: 31910575a9de61e78065e93846e8e7a4894a18bf , < ae05340ccaa9d347fe85415609e075545bec589f (git)
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Linux Linux Affected: 2.6.24
Unaffected: 0 , < 2.6.24 (semver)
Unaffected: 5.10.253 , ≤ 5.10.* (semver)
Unaffected: 5.15.203 , ≤ 5.15.* (semver)
Unaffected: 6.1.168 , ≤ 6.1.* (semver)
Unaffected: 6.6.134 , ≤ 6.6.* (semver)
Unaffected: 6.12.81 , ≤ 6.12.* (semver)
Unaffected: 6.18.22 , ≤ 6.18.* (semver)
Unaffected: 6.19.12 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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  }
}


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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.