CVE-2026-68455 (GCVE-0-2026-68455)
Vulnerability from cvelistv5
Published
2026-08-15 05:51
Modified
2026-08-17 05:05
Severity ?
VLAI Severity ?
EPSS score ?
Summary
In the Linux kernel, the following vulnerability has been resolved:
liveupdate: validate session type before performing operation
The sessions ioctls are not applicable to all session types. PRESERVE_FD
is only applicable to outgoing sessions. RETRIEVE_FD and FINISH are only
valid for incoming session. Calling a incoming ioctl on an outgoing
session is invalid and can cause file handlers to run into unexpected
errors.
For example, a user can create a (outgoing) session, preserve a memfd,
and then immediately do a retrieve without doing a kexec in between.
This would result in memfd's retrieve handler to run. The handlers
expects to be called from a post-kexec context, and will try to do a
kho_restore_vmalloc() or kho_restore_folio() to try and restore memory.
KHO catches this (thanks to KHO_PAGE_MAGIC) and returns an error, but
since this is considered an internal error and KHO throws out a bunch of
WARN()s.
Associate a type with each ioctl op and validate the type in
luo_session_ioctl() before dispatching the ioctl handler to make sure
the op is being called for the right session type.
References
Impacted products
{
"containers": {
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"kernel/liveupdate/luo_session.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "3dc8a46d08a8a060d4128e9f497060b8d03c1595",
"status": "affected",
"version": "16cec0d265219f14a7fcebcc43aeb69205adba56",
"versionType": "git"
},
{
"lessThan": "507e3b479f9c6d85135eb5e1a77fb3fddb259ad8",
"status": "affected",
"version": "16cec0d265219f14a7fcebcc43aeb69205adba56",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"kernel/liveupdate/luo_session.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "6.19"
},
{
"lessThan": "6.19",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "7.1.*",
"status": "unaffected",
"version": "7.1.5",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.1.5",
"versionStartIncluding": "6.19",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.2",
"versionStartIncluding": "6.19",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nliveupdate: validate session type before performing operation\n\nThe sessions ioctls are not applicable to all session types. PRESERVE_FD\nis only applicable to outgoing sessions. RETRIEVE_FD and FINISH are only\nvalid for incoming session. Calling a incoming ioctl on an outgoing\nsession is invalid and can cause file handlers to run into unexpected\nerrors.\n\nFor example, a user can create a (outgoing) session, preserve a memfd,\nand then immediately do a retrieve without doing a kexec in between.\nThis would result in memfd\u0027s retrieve handler to run. The handlers\nexpects to be called from a post-kexec context, and will try to do a\nkho_restore_vmalloc() or kho_restore_folio() to try and restore memory.\n\nKHO catches this (thanks to KHO_PAGE_MAGIC) and returns an error, but\nsince this is considered an internal error and KHO throws out a bunch of\nWARN()s.\n\nAssociate a type with each ioctl op and validate the type in\nluo_session_ioctl() before dispatching the ioctl handler to make sure\nthe op is being called for the right session type."
}
],
"providerMetadata": {
"dateUpdated": "2026-08-17T05:05:55.589Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"references": [
{
"url": "https://git.kernel.org/stable/c/3dc8a46d08a8a060d4128e9f497060b8d03c1595"
},
{
"url": "https://git.kernel.org/stable/c/507e3b479f9c6d85135eb5e1a77fb3fddb259ad8"
}
],
"title": "liveupdate: validate session type before performing operation",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2026-68455",
"datePublished": "2026-08-15T05:51:16.745Z",
"dateReserved": "2026-07-30T09:28:09.395Z",
"dateUpdated": "2026-08-17T05:05:55.589Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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