{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "237fead619984cc48818fe12ee0ceada3f55b012"
            },
            {
              "fixed": "2cd21340163494d312836c77c9fbfe2530b3d075"
            },
            {
              "fixed": "e2152d491ae62d96a32ed59778680a242af1fbc6"
            },
            {
              "fixed": "d2802414081184f79a619ede178aeef3aa989793"
            },
            {
              "fixed": "33e050cac841498b5175f0f385eee903fd98863c"
            },
            {
              "fixed": "ccd13eff0e7356d2aa28b127b577e4e5ad4563f5"
            },
            {
              "fixed": "14cb36a500a5a3afbc955dbf69dabc565f1a3b26"
            },
            {
              "fixed": "a419c9ebfc9a40ee56aaad6dc68bfd67d400817b"
            },
            {
              "fixed": "5babe9c177c364521e3e682b949c5a8c47f4a441"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.6.19"
            },
            {
              "fixed": "5.10.270"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.221"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.188"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.157"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.109"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.50"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89607.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\necryptfs: reject oversized encrypted_key_size in parse_tag_3_packet\n\nparse_tag_3_packet() set encrypted_key_size from the Tag 3 packet body\nwithout bounding it against ECRYPTFS_MAX_KEY_BYTES (64). When\nencrypted_key_size \u003e 64, decrypt_passphrase_encrypted_session_key()\nsets decrypted_key_size = encrypted_key_size and performs two\nout-of-bounds writes:\n\n1. crypto_skcipher_decrypt() writes encrypted_key_size bytes into\n   decrypted_key[64] via scatterlist, overflowing into the parent\n   ecryptfs_auth_tok struct.\n2. memcpy(crypt_stat-\u003ekey, decrypted_key, decrypted_key_size) writes\n   into crypt_stat-\u003ekey[64], corrupting root_iv, keysig_list, and\n   mutexes in ecryptfs_crypt_stat.\n\nOnly AES-192 (cipher code 0x08) enables this because it sets\ncrypt_stat-\u003ekey_size = 24 independently of encrypted_key_size,\nallowing crypto_skcipher_setkey() to succeed while encrypted_key_size\nexceeds ECRYPTFS_MAX_KEY_BYTES.\n\nThe PKI decryption path (parse_tag_65_packet) already validates\ndecrypted_key_size \u003c= ECRYPTFS_MAX_KEY_BYTES; the passphrase path\nomits this check.\n\nBound encrypted_key_size against ECRYPTFS_MAX_KEY_BYTES (64) rather\nthan ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES (512). The 64-byte limit also\nprotects the 512-byte encrypted_key[] buffer, so the former 512-byte\ncheck is removed as redundant.\n\n[tyhicks: Adjust the code comment to refer to macros representing the\n buffer sizes rather than mentioning the buffer size values since they\n may change in the future]",
  "id": "CVE-2026-89607",
  "modified": "2026-09-16T03:30:53.805525962Z",
  "published": "2026-09-11T19:45:09.583Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/14cb36a500a5a3afbc955dbf69dabc565f1a3b26"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2cd21340163494d312836c77c9fbfe2530b3d075"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/33e050cac841498b5175f0f385eee903fd98863c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5babe9c177c364521e3e682b949c5a8c47f4a441"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a419c9ebfc9a40ee56aaad6dc68bfd67d400817b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ccd13eff0e7356d2aa28b127b577e4e5ad4563f5"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d2802414081184f79a619ede178aeef3aa989793"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e2152d491ae62d96a32ed59778680a242af1fbc6"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89607.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-89607"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "ecryptfs: reject oversized encrypted_key_size in parse_tag_3_packet"
}