ecryptfs: reject oversized encrypted_key_size in parse_tag_3_packet
In the Linux kernel, the following vulnerability has been resolved: ecryptfs: reject oversized encrypted_key_size in parse_tag_3_packet parse_tag_3_packet() set encrypted_key_size from the Tag 3 packet body without bounding it against ECRYPTFS_MAX_KEY_BYTES (64). When encrypted_key_size > 64, decrypt_passphrase_encrypted_session_key() sets decrypted_key_size = encrypted_key_size and performs two out-of-bounds writes: 1. crypto_skcipher_decrypt() writes encrypted_key_size bytes into decrypted_key[64] via scatterlist, overflowing into the parent ecryptfs_auth_tok struct. 2. memcpy(crypt_stat->key, decrypted_key, decrypted_key_size) writes into crypt_stat->key[64], corrupting root_iv, keysig_list, and mutexes in ecryptfs_crypt_stat. Only AES-192 (cipher code 0x08) enables this because it sets crypt_stat->key_size = 24 independently of encrypted_key_size, allowing crypto_skcipher_setkey() to succeed while encrypted_key_size exceeds ECRYPTFS_MAX_KEY_BYTES. The PKI decryption path (parse_tag_65_packet) already validates decrypted_key_size <= ECRYPTFS_MAX_KEY_BYTES; the passphrase path omits this check. Bound encrypted_key_size against ECRYPTFS_MAX_KEY_BYTES (64) rather than ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES (512). The 64-byte limit also protects the 512-byte encrypted_key[] buffer, so the former 512-byte check is removed as redundant. [tyhicks: Adjust the code comment to refer to macros representing the buffer sizes rather than mentioning the buffer size values since they may change
CVE-2026-89607
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-89607
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "237fead619984cc48818fe12ee0ceada3f55b012",
"lessThan": "2cd21340163494d312836c77c9fbfe2530b3d075",
"versionType": "git"
},
{
"status": "affected",
"version": "237fead619984cc48818fe12ee0ceada3f55b012",
"lessThan": "e2152d491ae62d96a32ed59778680a242af1fbc6",
"versionType": "git"
},
{
"status": "affected",
"version": "237fead619984cc48818fe12ee0ceada3f55b012",
"lessThan": "d2802414081184f79a619ede178aeef3aa989793",
"versionType": "git"
},
{
"status": "affected",
"version": "237fead619984cc48818fe12ee0ceada3f55b012",
"lessThan": "33e050cac841498b5175f0f385eee903fd98863c",
"versionType": "git"
},
{
"status": "affected",
"version": "237fead619984cc48818fe12ee0ceada3f55b012",
"lessThan": "ccd13eff0e7356d2aa28b127b577e4e5ad4563f5",
"versionType": "git"
},
{
"status": "affected",
"version": "237fead619984cc48818fe12ee0ceada3f55b012",
"lessThan": "14cb36a500a5a3afbc955dbf69dabc565f1a3b26",
"versionType": "git"
},
{
"status": "affected",
"version": "237fead619984cc48818fe12ee0ceada3f55b012",
"lessThan": "a419c9ebfc9a40ee56aaad6dc68bfd67d400817b",
"versionType": "git"
},
{
"status": "affected",
"version": "237fead619984cc48818fe12ee0ceada3f55b012",
"lessThan": "5babe9c177c364521e3e682b949c5a8c47f4a441",
"versionType": "git"
}
],
"programFiles": [
"fs/ecryptfs/keystore.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "2.6.19"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "2.6.19",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.270",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.221",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.188",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.157",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.109",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.50",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.4",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"fs/ecryptfs/keystore.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-89607
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #35113 · Revision 1
- Added to Heist Feed
- Publisher date