CVE-2026-43364

In the Linux kernel, the following vulnerability has been resolved: ublk: fix NULL pointer dereference in ublk_ctrl_set_size() ublk_ctrl_set_size() unconditionally dereferences ub->ub_disk via set_capacity_and_notify() without checking if it is NULL. ub->ub_disk is NULL before UBLK_CMD_START_DEV completes (it is only assigned in ublk_ctrl_start_dev()) and after UBLK_CMD_STOP_DEV runs (ublk_detach_disk() sets it to NULL). Since the UBLK_CMD_UPDATE_SIZE handler performs no state validation, a user can trigger a NULL pointer dereference by sending UPDATE_SIZE to a device that has been added but not yet started, or one that has been stopped. Fix this by checking ub->ub_disk under ub->mutex before dereferencing it, and returning -ENODEV if the disk is not available.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/25966fc097691e5c925ad080f64a2f19c5fd940a	Patch
https://git.kernel.org/stable/c/c28d945bfa92e15147e93b73f95345b9bec979b0	Patch
https://git.kernel.org/stable/c/f13fe6794726755a43090cb680c4c58cea6aa5f1	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc1::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc2::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc3::::::

History

No history.

Information

Published : 2026-05-08 15:16

Updated : 2026-06-17 10:49

NVD link : CVE-2026-43364

Mitre link : CVE-2026-43364

CVE.ORG link : CVE-2026-43364

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-476

NULL Pointer Dereference

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