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CVE-2026-89776

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: vxlan: vnifilter: enforce exact length of GROUP/GROUP6 attributes The VXLAN VNI filter entry policy declares the GROUP/GROUP6 address attributes as NLA_BINARY with only a maximum length, so validate_nla() accepts a payload shorter than the address. The GROUP consumer reads it with nla_get_in_addr(), an unconditional 4-byte load, so a short attribute over-reads up to 3 bytes of uninitialised slab data, which are stored into remote_ip and echoed back via RTM_GETTUNNEL, disclosing kernel memory. Switch both entries to NLA_POLICY_EXACT_LEN() so the validator rejects any GROUP/GROUP6 that is not exactly 4 / 16 bytes; a valid address is always sent at full width.

Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-16 09:17:07.950000
Last modified
2026-10-19 09:18:20.823000
View original CVE JSON
{
  "id": "CVE-2026-89776",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-16T09:17:07.950",
  "lastModified": "2026-10-19T09:18:20.823",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvxlan: vnifilter: enforce exact length of GROUP/GROUP6 attributes\n\nThe VXLAN VNI filter entry policy declares the GROUP/GROUP6 address\nattributes as NLA_BINARY with only a maximum length, so validate_nla()\naccepts a payload shorter than the address. The GROUP consumer reads it\nwith nla_get_in_addr(), an unconditional 4-byte load, so a short\nattribute over-reads up to 3 bytes of uninitialised slab data, which are\nstored into remote_ip and echoed back via RTM_GETTUNNEL, disclosing\nkernel memory.\n\nSwitch both entries to NLA_POLICY_EXACT_LEN() so the validator rejects\nany GROUP/GROUP6 that is not exactly 4 / 16 bytes; a valid address is\nalways sent at full width."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/net/vxlan/vxlan_vnifilter.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "f9c4bb0b245cee35ef66f75bf409c9573d934cf9",
              "lessThan": "e12c4663529699f457b2988c1dfedf4d13b3b3be",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "f9c4bb0b245cee35ef66f75bf409c9573d934cf9",
              "lessThan": "47bfcc871576eaef6c8edab6749acd4b317306ea",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "f9c4bb0b245cee35ef66f75bf409c9573d934cf9",
              "lessThan": "a9ec10815199f9879ba080241dc555efb1daf324",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "f9c4bb0b245cee35ef66f75bf409c9573d934cf9",
              "lessThan": "daebc7064a1b4c12c98e52c4bceede7f2fcd573c",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "f9c4bb0b245cee35ef66f75bf409c9573d934cf9",
              "lessThan": "ad32e564c62ebf5ba76dd60a22af52c69d54d17b",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "f9c4bb0b245cee35ef66f75bf409c9573d934cf9",
              "lessThan": "984f831dda31b3a18f47454cf64989f65402879e",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/net/vxlan/vxlan_vnifilter.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "5.18",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "5.18",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.188",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.157",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.110",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.52",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.6",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/47bfcc871576eaef6c8edab6749acd4b317306ea",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/984f831dda31b3a18f47454cf64989f65402879e",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/a9ec10815199f9879ba080241dc555efb1daf324",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ad32e564c62ebf5ba76dd60a22af52c69d54d17b",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/daebc7064a1b4c12c98e52c4bceede7f2fcd573c",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/e12c4663529699f457b2988c1dfedf4d13b3b3be",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}