CVE-2026-72086
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: scsi: xen: scsiback: Free the command tag on the TMR submit-failure path scsiback_device_action() obtains a command tag in scsiback_get_pend_req() and submits a task-management request with target_submit_tmr(). When target_submit_tmr() fails it returns < 0 and scsiback jumps to the err: label, which sends a response but frees nothing, leaking the tag. Impact: a pvSCSI guest can leak the command tags of a LUN's session, stopping the LUN, by issuing VSCSIIF_ACT_SCSI_ABORT or RESET requests whenever target_submit_tmr() fails. transport_generic_free_cmd() cannot be used here. By the time target_submit_tmr() returns an error it has already run __target_init_cmd() (so se_cmd->cmd_kref is one, not zero), and on its target_get_sess_cmd() error path it has freed se_cmd->se_tmr_req via core_tmr_release_req() while leaving SCF_SCSI_TMR_CDB set and the pointer dangling. Letting the command release run target_free_cmd_mem() would then double-free se_tmr_req. Use the same helper, which returns just the tag, on this path too.
Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-08-15 06:21:22.593000
Last modified
2026-11-06 17:19:36.650000
View original CVE JSON
{
"id": "CVE-2026-72086",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-08-15T06:21:22.593",
"lastModified": "2026-11-06T17:19:36.650",
"vulnStatus": "Received",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nscsi: xen: scsiback: Free the command tag on the TMR submit-failure path\n\nscsiback_device_action() obtains a command tag in\nscsiback_get_pend_req() and submits a task-management request with\ntarget_submit_tmr(). When target_submit_tmr() fails it returns < 0 and\nscsiback jumps to the err: label, which sends a response but frees\nnothing, leaking the tag.\n\nImpact: a pvSCSI guest can leak the command tags of a LUN's session,\nstopping the LUN, by issuing VSCSIIF_ACT_SCSI_ABORT or RESET requests\nwhenever target_submit_tmr() fails.\n\ntransport_generic_free_cmd() cannot be used here. By the time\ntarget_submit_tmr() returns an error it has already run\n__target_init_cmd() (so se_cmd->cmd_kref is one, not zero), and on its\ntarget_get_sess_cmd() error path it has freed se_cmd->se_tmr_req via\ncore_tmr_release_req() while leaving SCF_SCSI_TMR_CDB set and the\npointer dangling. Letting the command release run target_free_cmd_mem()\nwould then double-free se_tmr_req.\n\nUse the same helper, which returns just the tag, on this path too."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"drivers/xen/xen-scsiback.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "2dbcdf33dbf61f44b29adb52338282c3d7840d0e",
"lessThan": "4567ce79fe2f84c3dcc3a91b22a377cf482d33ad",
"versionType": "git",
"status": "affected"
},
{
"version": "2dbcdf33dbf61f44b29adb52338282c3d7840d0e",
"lessThan": "6c01f0439098f00a64b246dc27479602201382f7",
"versionType": "git",
"status": "affected"
},
{
"version": "2dbcdf33dbf61f44b29adb52338282c3d7840d0e",
"lessThan": "18d4f86816592586b38513543b5e1f9553bc271f",
"versionType": "git",
"status": "affected"
},
{
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"lessThan": "fbc1bdede66d0f2cde83b75d6524ce1a815bb69f",
"versionType": "git",
"status": "affected"
},
{
"version": "2dbcdf33dbf61f44b29adb52338282c3d7840d0e",
"lessThan": "255fb7b0cdc947b1c01929c7f133281342a3a6b5",
"versionType": "git",
"status": "affected"
},
{
"version": "2dbcdf33dbf61f44b29adb52338282c3d7840d0e",
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"versionType": "git",
"status": "affected"
},
{
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"lessThan": "66aefc277ebb796ec285d550305535dc3fc0179f",
"versionType": "git",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"drivers/xen/xen-scsiback.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "4.6",
"status": "affected"
},
{
"version": "0",
"lessThan": "4.6",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "5.15.212",
"lessThanOrEqual": "5.15.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.1.178",
"lessThanOrEqual": "6.1.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.6.145",
"lessThanOrEqual": "6.6.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.12.97",
"lessThanOrEqual": "6.12.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.18.40",
"lessThanOrEqual": "6.18.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.1.5",
"lessThanOrEqual": "7.1.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.2",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-11-06T16:51:20.477210Z",
"id": "CVE-2026-72086",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"references": [
{
"url": "https://git.kernel.org/stable/c/1357fb32d42ad8da193e6da285f09e6452feabda",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/18d4f86816592586b38513543b5e1f9553bc271f",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
"url": "https://git.kernel.org/stable/c/255fb7b0cdc947b1c01929c7f133281342a3a6b5",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/4567ce79fe2f84c3dcc3a91b22a377cf482d33ad",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/66aefc277ebb796ec285d550305535dc3fc0179f",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
"url": "https://git.kernel.org/stable/c/6c01f0439098f00a64b246dc27479602201382f7",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
"url": "https://git.kernel.org/stable/c/fbc1bdede66d0f2cde83b75d6524ce1a815bb69f",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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}