CVEvulnerability
CVE-2026-43364
5.5 MEDIUM
Official page ↗
- Status
- Analyzed
- Published
- 2026-05-08
- Last modified
- 2026-06-17
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- CVSS 3.1 ([email protected])
- 5.5 MEDIUM — CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Weaknesses
- CWE-476
Description
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.
Affected configurations
• linux linux kernel (>= 6.16 < 6.18.20)
• linux linux kernel (>= 6.19 < 6.19.9)
• linux linux kernel 7.0
Related
Weakness · CWE (1)
- CWE-476 NULL Pointer Dereference weakness