CVE intelligence

CVE-2026-52944

Vulnerability intelligence

Published Jun 24, 2026Sources checked Nov 12, 2026

5.5MEDIUMCVSS out of 10

What this means

Review the available evidence

CVE-2026-52944 and is rated Medium severity with a CVSS score of 5.5. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

What to do next

Remediation and response

Ubuntu Security Notices guidance

Vendor revision: Oct 9, 2026

Vendor remediation details

This update corrects flaws in the following subsystems: - ARM32 architecture; - ARM64 architecture; - MIPS architecture; - x86 architecture; - Intel NPU Driver; - Auxiliary display drivers; - Compressed RAM block device driver; - GPIO subsystem; - GPU drivers; - HID subsystem; - I2C subsystem; - IIO subsystem; - InfiniBand drivers; - Input Device core drivers; - Input Device (Mouse) drivers; - Multiple devices driver; - Media drivers; - Fastrpc Driver; - Ethernet bonding driver; - Network drivers; - Mellanox network drivers; - Microsoft Azure Network Adapter (MANA) driver; - Texas Instruments network drivers; - NVMEM (Non Volatile Memory) drivers; - Parport drivers; - SCSI subsystem; - SLIMbus drivers; - NVIDIA Tegra SoC drivers; - SPI subsystem; - Trusted Execution Environment drivers; -

Ubuntu Security Notices guidance

Vendor revision: Oct 9, 2026

Vendor remediation details

Ubuntu Security Notices guidance

Vendor revision: Oct 8, 2026

Vendor remediation details

This update corrects flaws in the following subsystems: - ARM64 architecture; - ARM32 architecture; - MIPS architecture; - PowerPC architecture; - x86 architecture; - Intel NPU Driver; - Compute Acceleration Framework; - Auxiliary display drivers; - Drivers core; - Compressed RAM block device driver; - Bluetooth drivers; - Arm Firmware Framework for ARMv8-A(FFA); - EFI core; - GPIO subsystem; - GPU drivers; - HID subsystem; - Hardware monitoring drivers; - I2C subsystem; - IIO subsystem; - InfiniBand drivers; - Input Device core drivers; - Input Device (Mouse) drivers; - Multiple devices driver; - Media drivers; - Fastrpc Driver; - Ethernet bonding driver; - Network drivers; - Mellanox network drivers; - Microsoft Azure Network Adapter (MANA) driver; - Texas Instruments network drivers; -

CISA KEVNot listedBased on the latest collected catalog

EPSS0.1%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-52944?

In the Linux kernel, the following vulnerability has been resolved:

ksmbd: fix FSCTL permission bypass by adding a permission check for FSCTL_SET_SPARSE

FSCTL_SET_SPARSE in fsctl_set_sparse() modifies the file's sparse attribute and saves it through xattr without any permission checks.

This exposes two issues:

1) A client on a read-only share can change the sparse attribute on files it opened, even though the share is read-only. Other FSCTL write operations already check test_tree_conn_flag(work->tcon, KSMBD_TREE_CONN_FLAG_WRITABLE), but FSCTL_SET_SPARSE does not.

2) Even on writable shares, clients without FILE_WRITE_DATA or FILE_WRITE_ATTRIBUTES access should not modify the sparse attribute. Similar handle-level checks exist in other functions but are missing here.

Add both share-level writable check and per-handle access check. Use goto out on error to avoid leaking file references.

Source: NVD