{"id":"CVE-2026-89607","revision":"1263661da79d4dda8fb23e6a0a0353e0","records":[{"revision":"1263661da79d4dda8fb23e6a0a0353e0","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-89607","aliases":[],"title":"ecryptfs: reject oversized encrypted_key_size in parse_tag_3_packet","description":"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 > 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->key, decrypted_key, decrypted_key_size) writes\n   into crypt_stat->key[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->key_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 <= 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]","state":0,"publishedAt":"2026-09-11T19:45:09.583+00:00","modifiedAt":"2026-10-19T08:49:39.398+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"fs/ecryptfs/keystore.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"237fead619984cc48818fe12ee0ceada3f55b012\",\n                            \"lessThan\": \"2cd21340163494d312836c77c9fbfe2530b3d075\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"237fead619984cc48818fe12ee0ceada3f55b012\",\n                            \"lessThan\": \"e2152d491ae62d96a32ed59778680a242af1fbc6\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"237fead619984cc48818fe12ee0ceada3f55b012\",\n                            \"lessThan\": \"d2802414081184f79a619ede178aeef3aa989793\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"237fead619984cc48818fe12ee0ceada3f55b012\",\n                            \"lessThan\": \"33e050cac841498b5175f0f385eee903fd98863c\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"237fead619984cc48818fe12ee0ceada3f55b012\",\n                            \"lessThan\": \"ccd13eff0e7356d2aa28b127b577e4e5ad4563f5\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"237fead619984cc48818fe12ee0ceada3f55b012\",\n                            \"lessThan\": \"14cb36a500a5a3afbc955dbf69dabc565f1a3b26\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"237fead619984cc48818fe12ee0ceada3f55b012\",\n                            \"lessThan\": \"a419c9ebfc9a40ee56aaad6dc68bfd67d400817b\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"237fead619984cc48818fe12ee0ceada3f55b012\",\n                            \"lessThan\": \"5babe9c177c364521e3e682b949c5a8c47f4a441\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"fs/ecryptfs/keystore.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"2.6.19\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"2.6.19\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.10.270\",\n                            \"lessThanOrEqual\": \"5.10.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.221\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.188\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.157\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.109\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.50\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.4\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/2cd21340163494d312836c77c9fbfe2530b3d075","https://git.kernel.org/stable/c/e2152d491ae62d96a32ed59778680a242af1fbc6","https://git.kernel.org/stable/c/d2802414081184f79a619ede178aeef3aa989793","https://git.kernel.org/stable/c/33e050cac841498b5175f0f385eee903fd98863c","https://git.kernel.org/stable/c/ccd13eff0e7356d2aa28b127b577e4e5ad4563f5","https://git.kernel.org/stable/c/14cb36a500a5a3afbc955dbf69dabc565f1a3b26","https://git.kernel.org/stable/c/a419c9ebfc9a40ee56aaad6dc68bfd67d400817b","https://git.kernel.org/stable/c/5babe9c177c364521e3e682b949c5a8c47f4a441"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-89607","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-89607","identifiers":["CVE-2026-89607"]},"retained":false,"historicalAffected":[]}],"coverage":[]}