{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "31910575a9de61e78065e93846e8e7a4894a18bf"
            },
            {
              "fixed": "1da9023f6b071a38e5430ffbce4b70b2b1ac4f9c"
            },
            {
              "fixed": "2fe4d0ba690a69ad6ae9f7ab9bdc96e02610b648"
            },
            {
              "fixed": "11d7fe97421cfc81549940c20ed5ac9472d6db05"
            },
            {
              "fixed": "7f56d87e527bb5a13c3e8b0d5840cb6332822f6d"
            },
            {
              "fixed": "4f810c686fde509d1cdaa706322d9d2531f8f1a4"
            },
            {
              "fixed": "b485eef3d97b7aae55ce669b6de555ec81f3d21c"
            },
            {
              "fixed": "ef3645606e4a635d5062a492f22b7f490852ee67"
            },
            {
              "fixed": "ae05340ccaa9d347fe85415609e075545bec589f"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.6.24"
            },
            {
              "fixed": "5.10.253"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.203"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.168"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.134"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.81"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.22"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "6.19.12"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43040.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: ipv6: ndisc: fix ndisc_ra_useropt to initialize nduseropt_padX fields to zero to prevent an info-leak\n\nWhen processing Router Advertisements with user options the kernel\nbuilds an RTM_NEWNDUSEROPT netlink message. The nduseroptmsg struct\nhas three padding fields that are never zeroed and can leak kernel data\n\nThe fix is simple, just zeroes the padding fields.",
  "id": "CVE-2026-43040",
  "modified": "2026-07-08T05:37:06.301809903Z",
  "published": "2026-05-01T14:15:37.364Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/11d7fe97421cfc81549940c20ed5ac9472d6db05"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1da9023f6b071a38e5430ffbce4b70b2b1ac4f9c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2fe4d0ba690a69ad6ae9f7ab9bdc96e02610b648"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4f810c686fde509d1cdaa706322d9d2531f8f1a4"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7f56d87e527bb5a13c3e8b0d5840cb6332822f6d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ae05340ccaa9d347fe85415609e075545bec589f"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b485eef3d97b7aae55ce669b6de555ec81f3d21c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ef3645606e4a635d5062a492f22b7f490852ee67"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43040.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-43040"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.7.5",
  "summary": "net: ipv6: ndisc: fix ndisc_ra_useropt to initialize nduseropt_padX fields to zero to prevent an info-leak"
}