CVE-2026-43336

Estado: AnalizadaAlta (7.5)—

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

lib/crypto: chacha: Zeroize permuted_state before it leaves scope

Since the ChaCha permutation is invertible, the local variable 'permuted_state' is sufficient to compute the original 'state', and thus the key, even after the permutation has been done.

While the kernel is quite inconsistent about zeroizing secrets on the stack (and some prominent userspace crypto libraries don't bother at all since it's not guaranteed to work anyway), the kernel does try to do it as a best practice, especially in cases involving the RNG.

Thus, explicitly zeroize 'permuted_state' before it goes out of scope.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Puntuación base: 7.5

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.58%
Percentil entre todas las CVEs puntuadas: 46
Fecha de la puntuación: 5/10/2026

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).

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

ExplotaciónT1190 Exploit Public-Facing Applicationinitial access45 %
Impacto principalT1552.007 Container APIcredential access75 %
Impacto secundarioT1040 Network Sniffingcredential access · discovery55 %

El kernel de Linux expone material criptográfico (clave ChaCha) en memoria por falta de zeroización; exploitable remotamente si se combina con lectura de memoria (T1552.007) o acceso físico/JTAG (T1040). Vector CVSS AV:N/AC:L/PR:N sugiere red, pero la vulnerabilidad per se es la no-limpieza de estad

Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Network Segmentation User Account Management Privileged Account Management Limit Access to Resource Over Network Vulnerability Scanning Multi-factor Authentication

Tecnologías afectadas (1)

Linux — Linux Kernel

CWE

NVD-CWE-noinfo

Referencias

JSON original (NVD)

Mostrar

{
  "id": "CVE-2026-43336",
  "cveTags": [],
  "metrics": {
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 7.5,
          "attackVector": "NETWORK",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "NONE",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 3.6,
        "exploitabilityScore": 3.9
      }
    ]
  },
  "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": "c08d0e647305c3f8f640010a56c9e4bafb9488d3",
              "lessThan": "e90ee961af515a484f091678ce58a4c3f7b73b02",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "c08d0e647305c3f8f640010a56c9e4bafb9488d3",
              "lessThan": "b416a4245f04a450c67a13e6d96056c37c5b33fe",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "c08d0e647305c3f8f640010a56c9e4bafb9488d3",
              "lessThan": "bd62d9b44464a6c20a34a74068e7a784d0afa04a",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "c08d0e647305c3f8f640010a56c9e4bafb9488d3",
              "lessThan": "066c760acead1fb743bae294dbd89f479ae43b9b",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "c08d0e647305c3f8f640010a56c9e4bafb9488d3",
              "lessThan": "1d761e5a7340c46479fb2399598f331e4fe2c633",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "c08d0e647305c3f8f640010a56c9e4bafb9488d3",
              "lessThan": "1933249263c3a98df79992f61a566476e4163bcc",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "c08d0e647305c3f8f640010a56c9e4bafb9488d3",
              "lessThan": "91999af43ca2125e3b2c18fcfc02912ada02efc3",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "c08d0e647305c3f8f640010a56c9e4bafb9488d3",
              "lessThan": "e5046823f8fa3677341b541a25af2fcb99a5b1e0",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "lib/crypto/chacha-block-generic.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.2"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "4.2",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "5.10.253",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "status": "unaffected",
              "version": "5.15.203",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "status": "unaffected",
              "version": "6.1.169",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "status": "unaffected",
              "version": "6.6.135",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "status": "unaffected",
              "version": "6.12.82",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "status": "unaffected",
              "version": "6.18.22",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "status": "unaffected",
              "version": "6.19.12",
              "versionType": "semver",
              "lessThanOrEqual": "6.19.*"
            },
            {
              "status": "unaffected",
              "version": "7.0",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "lib/crypto/chacha-block-generic.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-05-08T14:16:43.383",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/066c760acead1fb743bae294dbd89f479ae43b9b",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/1933249263c3a98df79992f61a566476e4163bcc",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/1d761e5a7340c46479fb2399598f331e4fe2c633",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/91999af43ca2125e3b2c18fcfc02912ada02efc3",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b416a4245f04a450c67a13e6d96056c37c5b33fe",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/bd62d9b44464a6c20a34a74068e7a784d0afa04a",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/e5046823f8fa3677341b541a25af2fcb99a5b1e0",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/e90ee961af515a484f091678ce58a4c3f7b73b02",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "NVD-CWE-noinfo"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nlib/crypto: chacha: Zeroize permuted_state before it leaves scope\n\nSince the ChaCha permutation is invertible, the local variable\n'permuted_state' is sufficient to compute the original 'state', and thus\nthe key, even after the permutation has been done.\n\nWhile the kernel is quite inconsistent about zeroizing secrets on the\nstack (and some prominent userspace crypto libraries don't bother at all\nsince it's not guaranteed to work anyway), the kernel does try to do it\nas a best practice, especially in cases involving the RNG.\n\nThus, explicitly zeroize 'permuted_state' before it goes out of scope."
    }
  ],
  "lastModified": "2026-06-17T10:49:24.387",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "CC85AD7F-B910-43F1-9A7F-94BC2781DACB",
              "versionEndExcluding": "5.10.253",
              "versionStartIncluding": "4.2"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "20DDB3E9-AABF-4107-ADB0-5362AA067045",
              "versionEndExcluding": "5.15.203",
              "versionStartIncluding": "5.11"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "DBEC0E5D-641C-4E98-A6D9-5799B10CE451",
              "versionEndExcluding": "6.1.169",
              "versionStartIncluding": "5.16"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "15C1A1B2-14EE-494C-AF3E-D5A7BA640B39",
              "versionEndExcluding": "6.6.135",
              "versionStartIncluding": "6.2"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "02904CAE-71D2-45B3-9EC3-F6A9D18B6307",
              "versionEndExcluding": "6.12.82",
              "versionStartIncluding": "6.7"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "C9DF8BCE-36D3-475D-9D21-19E4F02F9029",
              "versionEndExcluding": "6.18.22",
              "versionStartIncluding": "6.13"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "0A2B9540-02D5-41B4-B16A-82AF66FD4F36",
              "versionEndExcluding": "6.19.12",
              "versionStartIncluding": "6.19"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "F253B622-8837-4245-BCE5-A7BF8FC76A16"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "4AE85AD8-4641-4E7C-A2F4-305E2CD9EE64"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "F666C8D8-6538-46D4-B318-87610DE64C34"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "02259FDA-961B-47BC-AE7F-93D7EC6E90C2"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "58A9FEFF-C040-420D-8F0A-BFDAAA1DF258"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "1D2315C0-D46F-4F85-9754-F9E5E11374A6"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}