« Volver al listado

CVE-2026-45966

Estado: AnalizadaMedia (5.5)—

In the Linux kernel, the following vulnerability has been resolved:

apparmor: fix NULL pointer dereference in __unix_needs_revalidation

When receiving file descriptors via SCM_RIGHTS, both the socket pointer and the socket's sk pointer can be NULL during socket setup or teardown, causing NULL pointer dereferences in __unix_needs_revalidation().

This is a regression in AppArmor 5.0.0 (kernel 6.17+) where the new __unix_needs_revalidation() function was added without proper NULL checks.

The function dereferences sock->sk->sk_family without checking if either sock or sock->sk is NULL first.

Add NULL checks for both sock and sock->sk before accessing sk_family.

Detalles técnicos trazas, registros y código del informe original
The crash manifests as:
  BUG: kernel NULL pointer dereference, address: 0x0000000000000018
  RIP: aa_file_perm+0xb7/0x3b0 (or +0xbe/0x3b0, +0xc0/0x3e0)
  Call Trace:
   apparmor_file_receive+0x42/0x80
   security_file_receive+0x2e/0x50
   receive_fd+0x1d/0xf0
   scm_detach_fds+0xad/0x1c0

CVSS

Probabilidad de explotación (EPSS)

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

Tecnologías afectadas (1)

Linux — Linux Kernel

CWE

Referencias

JSON original (NVD)

Mostrar
{
  "id": "CVE-2026-45966",
  "cveTags": [],
  "metrics": {
    "cvssMetricV31": [
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 5.5,
          "attackVector": "LOCAL",
          "baseSeverity": "MEDIUM",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "NONE"
        },
        "impactScore": 3.6,
        "exploitabilityScore": 1.8
      }
    ]
  },
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "88fec3526e84123997ecebd6bb6778eb4ce779b7",
              "lessThan": "fea017a7f6abe179decf575a2d8464c74edb3964",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "88fec3526e84123997ecebd6bb6778eb4ce779b7",
              "lessThan": "e85bc9101afc4202aa2269967ce9d3ffbecd0994",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "88fec3526e84123997ecebd6bb6778eb4ce779b7",
              "lessThan": "e2938ad00b21340c0362562dfedd7cfec0554d67",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "security/apparmor/file.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.17"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "6.17",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "6.18.14",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "status": "unaffected",
              "version": "6.19.4",
              "versionType": "semver",
              "lessThanOrEqual": "6.19.*"
            },
            {
              "status": "unaffected",
              "version": "7.0",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "security/apparmor/file.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-05-27T14:17:13.460",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/e2938ad00b21340c0362562dfedd7cfec0554d67",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/e85bc9101afc4202aa2269967ce9d3ffbecd0994",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/fea017a7f6abe179decf575a2d8464c74edb3964",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "CWE-476"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\napparmor: fix NULL pointer dereference in __unix_needs_revalidation\n\nWhen receiving file descriptors via SCM_RIGHTS, both the socket pointer\nand the socket's sk pointer can be NULL during socket setup or teardown,\ncausing NULL pointer dereferences in __unix_needs_revalidation().\n\nThis is a regression in AppArmor 5.0.0 (kernel 6.17+) where the new\n__unix_needs_revalidation() function was added without proper NULL checks.\n\nThe crash manifests as:\n  BUG: kernel NULL pointer dereference, address: 0x0000000000000018\n  RIP: aa_file_perm+0xb7/0x3b0 (or +0xbe/0x3b0, +0xc0/0x3e0)\n  Call Trace:\n   apparmor_file_receive+0x42/0x80\n   security_file_receive+0x2e/0x50\n   receive_fd+0x1d/0xf0\n   scm_detach_fds+0xad/0x1c0\n\nThe function dereferences sock->sk->sk_family without checking if either\nsock or sock->sk is NULL first.\n\nAdd NULL checks for both sock and sock->sk before accessing sk_family."
    }
  ],
  "lastModified": "2026-06-17T10:52:48.810",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "26EE06AD-A558-4B3A-9C7C-9EBD5CF65449",
              "versionEndExcluding": "6.18.14",
              "versionStartIncluding": "6.17"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "672A3E79-EC03-479D-8503-361DFBDC8092",
              "versionEndExcluding": "6.19.4",
              "versionStartIncluding": "6.19"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}