CVE-2026-72086

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.

Gravité et risque d'exploitation

CVE-2026-72086 obtient un score CVSS de 0.0/10, soit une gravité non évaluée. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.21 %, ce qui la place devant 10.7 % des CVE référencées.

Que faire ?

• Vérifiez si Linux (versions <6c01f0439098f00a64b246dc27479602201382f7, <=6.1.*, 7.1.5, 6.18.40, <=6.12.*, <4567ce79fe2f84c3dcc3a91b22a377cf482d33ad, <255fb7b0cdc947b1c01929c7f133281342a3a6b5, 0, <4.6, <=7.1.*, 6.1.178, <fbc1bdede66d0f2cde83b75d6524ce1a815bb69f, 6.12.97, <=6.6.*, 4.6, <=6.18.*, 5.15.212, 2dbcdf33dbf61f44b29adb52338282c3d7840d0e, 6.6.145, <18d4f86816592586b38513543b5e1f9553bc271f, <=*, <=5.15.*, <66aefc277ebb796ec285d550305535dc3fc0179f, 7.2, <1357fb32d42ad8da193e6da285f09e6452feabda) est présent sur votre parc.
• Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
• À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
• Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.

Références

• https://git.kernel.org/stable/c/4567ce79fe2f84c3dcc3a91b22a377cf482d33ad
• https://git.kernel.org/stable/c/6c01f0439098f00a64b246dc27479602201382f7
• https://git.kernel.org/stable/c/18d4f86816592586b38513543b5e1f9553bc271f
• https://git.kernel.org/stable/c/fbc1bdede66d0f2cde83b75d6524ce1a815bb69f
• https://git.kernel.org/stable/c/255fb7b0cdc947b1c01929c7f133281342a3a6b5
• https://git.kernel.org/stable/c/1357fb32d42ad8da193e6da285f09e6452feabda
• https://git.kernel.org/stable/c/66aefc277ebb796ec285d550305535dc3fc0179f