CVE-2026-98723
In the Linux kernel, the following vulnerability has been resolved:
nvmet: copy the hostid into the ctrl before creating PR pc_refs
Commit 6202783184bf ("nvmet: Improve nvmet_alloc_ctrl() interface and implementation") added a second uuid_copy() of args->hostid near the end of nvmet_alloc_ctrl(), and commit 7b658153f1b8 ("nvmet: Remove duplicate uuid_copy") removed the original copy that sat before nvmet_ctrl_init_pr() instead of the new one.
Since then nvmet_ctrl_init_pr() snapshots ctrl->hostid into the per-controller per-namespace reservation refs while the uuid_copy() from the connect data runs later, after the controller is published. The ctrl is allocated with kzalloc(), so every pc_ref created on this path stores the nil UUID.
Read full descriptionShow less
pc_ref->hostid has a single consumer: nvmet_pr_set_ctrl_to_abort() matches it against the preempted registrant's hostid to kill and drain the victim's in-flight I/O for Preempt and Abort. The match can never hit with the nil UUID, so whenever a namespace with reservations enabled exists before a host connects, which includes every reconnect, Preempt and Abort silently degrades into a plain Preempt: the preempting host sees success while the victim's in-flight I/O is still in the air.
Copy the hostid where the rest of the connect data is consumed, before the controller is published and before nvmet_ctrl_init_pr() takes its snapshot.
CVSS
NVD hasn't assigned a CVSS score to this CVE (common since the April 2026 policy change).
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days
- 0.20 %
- Percentile among all scored CVEs
- 9
- Score date
- 10/20/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (1)
⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.
References
Raw JSON (NVD)
Show
{
"id": "CVE-2026-98723",
"cveTags": [],
"metrics": {},
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "7b658153f1b8a79ed98980f2fef7b92a66aeb9cd",
"lessThan": "d3d6d7efdacc08616d23b3ac42272a494951dc0f",
"versionType": "git"
},
{
"status": "affected",
"version": "7b658153f1b8a79ed98980f2fef7b92a66aeb9cd",
"lessThan": "23194531595c5d1d4454e3a607b0c8fc0c4e8695",
"versionType": "git"
},
{
"status": "affected",
"version": "7b658153f1b8a79ed98980f2fef7b92a66aeb9cd",
"lessThan": "5211fed41d7ec90e9ab7239dc4bffffe4d0b2b62",
"versionType": "git"
}
],
"programFiles": [
"drivers/nvme/target/core.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": "6.18.56",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.10",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"drivers/nvme/target/core.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-10-18T16:17:25.917",
"references": [
{
"url": "https://git.kernel.org/stable/c/23194531595c5d1d4454e3a607b0c8fc0c4e8695",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/5211fed41d7ec90e9ab7239dc4bffffe4d0b2b62",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/d3d6d7efdacc08616d23b3ac42272a494951dc0f",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Received",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnvmet: copy the hostid into the ctrl before creating PR pc_refs\n\nCommit 6202783184bf (\"nvmet: Improve nvmet_alloc_ctrl() interface and\nimplementation\") added a second uuid_copy() of args->hostid near the end\nof nvmet_alloc_ctrl(), and commit 7b658153f1b8 (\"nvmet: Remove duplicate\nuuid_copy\") removed the original copy that sat before\nnvmet_ctrl_init_pr() instead of the new one.\n\nSince then nvmet_ctrl_init_pr() snapshots ctrl->hostid into the\nper-controller per-namespace reservation refs while the uuid_copy()\nfrom the connect data runs later, after the controller is published.\nThe ctrl is allocated with kzalloc(), so every pc_ref created on this\npath stores the nil UUID.\n\npc_ref->hostid has a single consumer: nvmet_pr_set_ctrl_to_abort()\nmatches it against the preempted registrant's hostid to kill and drain\nthe victim's in-flight I/O for Preempt and Abort. The match can never\nhit with the nil UUID, so whenever a namespace with reservations\nenabled exists before a host connects, which includes every reconnect,\nPreempt and Abort silently degrades into a plain Preempt: the\npreempting host sees success while the victim's in-flight I/O is still\nin the air.\n\nCopy the hostid where the rest of the connect data is consumed, before\nthe controller is published and before nvmet_ctrl_init_pr() takes its\nsnapshot."
}
],
"lastModified": "2026-10-19T10:19:36.500",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}