CVE-2026-72086
scsi: xen: scsiback: Free the command tag on the TMR submit-failure path
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.
INFO
Published Date :
Aug. 15, 2026, 6:21 a.m.
Last Modified :
Aug. 17, 2026, 6:18 a.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
- Update the Linux kernel to the latest version.
- Apply the vendor-supplied patch for scsiback.
- Verify memory management after the update.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-72086.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-72086 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-72086
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-72086 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-72086 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 17, 2026
Action Type Old Value New Value Changed Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '2dbcdf33dbf61f44b29adb52338282c3d7840d0e', 'lessThan': '4567ce79fe2f84c3dcc3a91b22a377cf482d33ad', 'versionType': 'git'}, {'status': 'affected', 'version': '2dbcdf33dbf61f44b29adb52338282c3d7840d0e', 'lessThan': '6c01f0439098f00a64b246dc27479602201382f7', 'versionType': 'git'}, {'status': 'affected', 'version': '2dbcdf33dbf61f44b29adb52338282c3d7840d0e', 'lessThan': '18d4f86816592586b38513543b5e1f9553bc271f', 'versionType': 'git'}, {'status': 'affected', 'version': '2dbcdf33dbf61f44b29adb52338282c3d7840d0e', 'lessThan': 'fbc1bdede66d0f2cde83b75d6524ce1a815bb69f', 'versionType': 'git'}, {'status': 'affected', 'version': '2dbcdf33dbf61f44b29adb52338282c3d7840d0e', 'lessThan': '255fb7b0cdc947b1c01929c7f133281342a3a6b5', 'versionType': 'git'}, {'status': 'affected', 'version': '2dbcdf33dbf61f44b29adb52338282c3d7840d0e', 'lessThan': '1357fb32d42ad8da193e6da285f09e6452feabda', 'versionType': 'git'}, {'status': 'affected', 'version': '2dbcdf33dbf61f44b29adb52338282c3d7840d0e', 'lessThan': '66aefc277ebb796ec285d550305535dc3fc0179f', 'versionType': 'git'}], 'programFiles': ['drivers/xen/xen-scsiback.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.6'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.6', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '5.15.212', 'versionType': 'semver', 'lessThanOrEqual': '5.15.*'}, {'status': 'unaffected', 'version': '6.1.178', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.145', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.97', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.40', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc4', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['drivers/xen/xen-scsiback.c'], 'defaultStatus': 'affected'}] [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '2dbcdf33dbf61f44b29adb52338282c3d7840d0e', 'lessThan': '4567ce79fe2f84c3dcc3a91b22a377cf482d33ad', 'versionType': 'git'}, {'status': 'affected', 'version': '2dbcdf33dbf61f44b29adb52338282c3d7840d0e', 'lessThan': '6c01f0439098f00a64b246dc27479602201382f7', 'versionType': 'git'}, {'status': 'affected', 'version': '2dbcdf33dbf61f44b29adb52338282c3d7840d0e', 'lessThan': '18d4f86816592586b38513543b5e1f9553bc271f', 'versionType': 'git'}, {'status': 'affected', 'version': '2dbcdf33dbf61f44b29adb52338282c3d7840d0e', 'lessThan': 'fbc1bdede66d0f2cde83b75d6524ce1a815bb69f', 'versionType': 'git'}, {'status': 'affected', 'version': '2dbcdf33dbf61f44b29adb52338282c3d7840d0e', 'lessThan': '255fb7b0cdc947b1c01929c7f133281342a3a6b5', 'versionType': 'git'}, {'status': 'affected', 'version': '2dbcdf33dbf61f44b29adb52338282c3d7840d0e', 'lessThan': '1357fb32d42ad8da193e6da285f09e6452feabda', 'versionType': 'git'}, {'status': 'affected', 'version': '2dbcdf33dbf61f44b29adb52338282c3d7840d0e', 'lessThan': '66aefc277ebb796ec285d550305535dc3fc0179f', 'versionType': 'git'}], 'programFiles': ['drivers/xen/xen-scsiback.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.6'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.6', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '5.15.212', 'versionType': 'semver', 'lessThanOrEqual': '5.15.*'}, {'status': 'unaffected', 'version': '6.1.178', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.145', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.97', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.40', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['drivers/xen/xen-scsiback.c'], 'defaultStatus': 'affected'}] -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 15, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '2dbcdf33dbf61f44b29adb52338282c3d7840d0e', 'lessThan': '4567ce79fe2f84c3dcc3a91b22a377cf482d33ad', 'versionType': 'git'}, {'status': 'affected', 'version': '2dbcdf33dbf61f44b29adb52338282c3d7840d0e', 'lessThan': '6c01f0439098f00a64b246dc27479602201382f7', 'versionType': 'git'}, {'status': 'affected', 'version': '2dbcdf33dbf61f44b29adb52338282c3d7840d0e', 'lessThan': '18d4f86816592586b38513543b5e1f9553bc271f', 'versionType': 'git'}, {'status': 'affected', 'version': '2dbcdf33dbf61f44b29adb52338282c3d7840d0e', 'lessThan': 'fbc1bdede66d0f2cde83b75d6524ce1a815bb69f', 'versionType': 'git'}, {'status': 'affected', 'version': '2dbcdf33dbf61f44b29adb52338282c3d7840d0e', 'lessThan': '255fb7b0cdc947b1c01929c7f133281342a3a6b5', 'versionType': 'git'}, {'status': 'affected', 'version': '2dbcdf33dbf61f44b29adb52338282c3d7840d0e', 'lessThan': '1357fb32d42ad8da193e6da285f09e6452feabda', 'versionType': 'git'}, {'status': 'affected', 'version': '2dbcdf33dbf61f44b29adb52338282c3d7840d0e', 'lessThan': '66aefc277ebb796ec285d550305535dc3fc0179f', 'versionType': 'git'}], 'programFiles': ['drivers/xen/xen-scsiback.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.6'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.6', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '5.15.212', 'versionType': 'semver', 'lessThanOrEqual': '5.15.*'}, {'status': 'unaffected', 'version': '6.1.178', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.145', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.97', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.40', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc4', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['drivers/xen/xen-scsiback.c'], 'defaultStatus': 'affected'}] Added 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. Added Reference https://git.kernel.org/stable/c/1357fb32d42ad8da193e6da285f09e6452feabda Added Reference https://git.kernel.org/stable/c/18d4f86816592586b38513543b5e1f9553bc271f Added Reference https://git.kernel.org/stable/c/255fb7b0cdc947b1c01929c7f133281342a3a6b5 Added Reference https://git.kernel.org/stable/c/4567ce79fe2f84c3dcc3a91b22a377cf482d33ad Added Reference https://git.kernel.org/stable/c/66aefc277ebb796ec285d550305535dc3fc0179f Added Reference https://git.kernel.org/stable/c/6c01f0439098f00a64b246dc27479602201382f7 Added Reference https://git.kernel.org/stable/c/fbc1bdede66d0f2cde83b75d6524ce1a815bb69f