CVE-2026-64439

{
  "id": "CVE-2026-64439",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-07-25T10:17:28.447",
  "lastModified": "2026-10-24T13:10:00.147",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: krb5 - filter out async aead implementations at alloc\n\nkrb5_aead_encrypt(), krb5_aead_decrypt() in rfc3961_simplified.c and\nrfc8009_encrypt(), rfc8009_decrypt() in rfc8009_aes2.c set a NULL\ncompletion callback and treat any negative return from\ncrypto_aead_{encrypt,decrypt}() as terminal, falling through to\nkfree_sensitive(buffer).  When the encrypt_name resolves to an\nasync AEAD instance the request returns -EINPROGRESS, the buffer\nis freed while the backend's worker still holds a pointer, and the\nworker dereferences the freed slab on completion.\n\nKASAN report under UML+SLUB with a synthetic async aead backend\nbound to krb5->encrypt_name:\n\n  BUG: KASAN: slab-use-after-free in t5_stub_complete+0x7d/0xc7\n\nThe helpers were written synchronously, so filter the async\ninstances out at allocation time instead of plumbing\ncrypto_wait_req() through every call site.\n\nReachable via net/rxrpc/rxgk.c, fs/afs/cm_security.c and\nnet/ceph/crypto.c on systems with an async AEAD provider bound to\nthe krb5 enctype name."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\ncrypto: krb5 - filtrar implementaciones AEAD asíncronas en la asignación\n\nkrb5_aead_encrypt(), krb5_aead_decrypt() en rfc3961_simplified.c y rfc8009_encrypt(), rfc8009_decrypt() en rfc8009_aes2.c establecen una devolución de llamada de finalización NULL y tratan cualquier retorno negativo de crypto_aead_{encrypt,decrypt}() como terminal, pasando a kfree_sensitive(buffer). Cuando el encrypt_name se resuelve en una instancia AEAD asíncrona, la solicitud devuelve -EINPROGRESS, el búfer es liberado mientras el trabajador del backend aún mantiene un puntero, y el trabajador desreferencia el slab liberado al finalizar.\n\nInforme KASAN bajo UML+SLUB con un backend AEAD asíncrono sintético vinculado a krb5  ->  encrypt_name:\n\nBUG: KASAN: uso después de liberación de slab en t5_stub_complete+0x7d/0xc7\n\nLos ayudantes fueron escritos de forma síncrona, así que filtrar las instancias asíncronas en el momento de la asignación en lugar de pasar crypto_wait_req() a través de cada sitio de llamada.\n\nAlcanzable a través de net/rxrpc/rxgk.c, fs/afs/cm_security.c y net/ceph/crypto.c en sistemas con un proveedor AEAD asíncrono vinculado al nombre de tipo de cifrado krb5."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "crypto/krb5/krb5_api.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "00244da40f7821b242c4612428d4192230dba27f",
              "lessThan": "ef6feb77e2d91761427c5b773edc9c97e1b706ad",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "00244da40f7821b242c4612428d4192230dba27f",
              "lessThan": "2b7bd6dccff14b8b632c5244f1fd506918077221",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "00244da40f7821b242c4612428d4192230dba27f",
              "lessThan": "6c9dddeb582fde005360f4fe02c760d45ca05fb5",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "crypto/krb5/krb5_api.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.15",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.15",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.39",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.1.4",
              "lessThanOrEqual": "7.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 9.8,
          "baseSeverity": "CRITICAL",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.9
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Primary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "versionStartIncluding": "6.15",
              "versionEndExcluding": "6.18.39",
              "matchCriteriaId": "1DA3E752-10DF-4260-A04E-FB6A07086768"
            },
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              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "versionStartIncluding": "6.19",
              "versionEndExcluding": "7.1.4",
              "matchCriteriaId": "6228DDD6-4557-4AA3-9F43-AB995D471E42"
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  ],
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/2b7bd6dccff14b8b632c5244f1fd506918077221",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ]
    },
    {
      "url": "https://git.kernel.org/stable/c/6c9dddeb582fde005360f4fe02c760d45ca05fb5",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
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    {
      "url": "https://git.kernel.org/stable/c/ef6feb77e2d91761427c5b773edc9c97e1b706ad",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
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}