isofs: validate block number from NFS file handle in isofs_export_iget
In the Linux kernel, the following vulnerability has been resolved: isofs: validate block number from NFS file handle in isofs_export_iget isofs_fh_to_dentry() and isofs_fh_to_parent() pass an attacker- controlled block number (ifid->block or ifid->parent_block) from the NFS file handle to isofs_export_iget(), which only rejects block == 0 before calling isofs_iget() and ultimately sb_bread(). A crafted file handle with fh_len sufficient to pass the check added by commit 0405d4b63d08 ("isofs: Prevent the use of too small fid") can still drive the server to read any in-range block on the backing device as if it were an iso_directory_record. That earlier fix was assigned CVE-2025-37780. sb_bread() on an out-of-range block returns NULL cleanly via the EIO path, so there is no memory-safety violation. For in-range reads of adjacent-partition data on the same block device, the unrelated bytes end up in iso_inode_info fields that reach the NFS client as dentry metadata. The deployment surface (isofs exported over NFS from loop-mounted images) is narrow and requires an authenticated NFS peer, but the malformed-file-handle class is reportable as hardening next to the existing CVE-2025-37780 fix. Reject block >= ISOFS_SB(sb)->s_nzones in isofs_export_iget() so the check covers both isofs_fh_to_dentry() and isofs_fh_to_parent() call sites with a single line.
CVE-2026-46124
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-2026-46124
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": "5e7de55602c61c8ff28db075cc49c8dd6989d7e0",
"lessThan": "ee0024f5a7e3c73aa253869fae9650ae054093ca",
"versionType": "git"
},
{
"status": "affected",
"version": "63d5a3e207bf315a32c7d16de6c89753a759f95a",
"lessThan": "31dbb4ba0f719ae7774e4c0c95172c9bf81692f5",
"versionType": "git"
},
{
"status": "affected",
"version": "0fdafdaef796816a9ed0fd7ac812932d569d9beb",
"lessThan": "908a76f0b1038035e6ebb4f2293ce079f92e0a02",
"versionType": "git"
},
{
"status": "affected",
"version": "952e7a7e317f126d0a2b879fc531b716932d5ffa",
"lessThan": "bb0988ed4f2e26d59bbb58f644cb3a55b7521e21",
"versionType": "git"
},
{
"status": "affected",
"version": "56dfffea9fd3be0b3795a9ca6401e133a8427e0b",
"lessThan": "0a1af74ae2177bda3aee0837a0546309aa539d0d",
"versionType": "git"
},
{
"status": "affected",
"version": "0405d4b63d082861f4eaff9d39c78ee9dc34f845",
"lessThan": "afbafeddf23db13fe2edb2d5c0bf4bbb13d7881b",
"versionType": "git"
},
{
"status": "affected",
"version": "0405d4b63d082861f4eaff9d39c78ee9dc34f845",
"lessThan": "4c721a1d9b3c4fcaf59cc9b2281e3ec5a043e1a6",
"versionType": "git"
},
{
"status": "affected",
"version": "0405d4b63d082861f4eaff9d39c78ee9dc34f845",
"lessThan": "24376458138387fb251e782e624c7776e9826796",
"versionType": "git"
},
{
"status": "affected",
"version": "ee01a309ebf598be1ff8174901ed6e91619f1749",
"versionType": "git"
},
{
"status": "affected",
"version": "007124c896e7d4614ac1f6bd4dedb975c35a2a8e",
"versionType": "git"
},
{
"status": "affected",
"version": "5.10.237",
"lessThan": "5.10.258",
"versionType": "semver"
},
{
"status": "affected",
"version": "5.15.181",
"lessThan": "5.15.209",
"versionType": "semver"
},
{
"status": "affected",
"version": "6.1.135",
"lessThan": "6.1.175",
"versionType": "semver"
},
{
"status": "affected",
"version": "6.6.88",
"lessThan": "6.6.140",
"versionType": "semver"
},
{
"status": "affected",
"version": "6.12.25",
"lessThan": "6.12.88",
"versionType": "semver"
},
{
"status": "affected",
"version": "5.4.293",
"lessThan": "5.5",
"versionType": "semver"
},
{
"status": "affected",
"version": "6.14.4",
"lessThan": "6.15",
"versionType": "semver"
}
],
"programFiles": [
"fs/isofs/export.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6.15"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "6.15",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.258",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.209",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.175",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.140",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.88",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.30",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.0.7",
"versionType": "semver",
"lessThanOrEqual": "7.0.*"
},
{
"status": "unaffected",
"version": "7.1",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"fs/isofs/export.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-46124
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #40136 · Revision 1
- Added to Heist Feed
- Publisher date