Use-after-free in Linux kernel - CVE-2026-90045

 

Use-after-free in Linux kernel - CVE-2026-90045

Published: September 16, 2026


Vulnerability identifier: #VU150247
CSH Severity: Low
CVSS v4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-90045
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a local user to compromise confidentiality, integrity, and availability.

The vulnerability exists due to a use-after-free in the FunctionFS asynchronous I/O handling in drivers/usb/gadget/function/f_fs.c when asynchronous read requests remain pending after the submitting task exits. A local user can queue an asynchronous read request and exit before completion handling finishes to compromise confidentiality, integrity, and availability.


Affected software

Linux kernel
Debian Linux
SUSE Linux Micro Extras
SUSE Linux Micro
Ubuntu
linux (Ubuntu package)
linux-oracle (Ubuntu package)
linux-gcp (Ubuntu package)
linux-aws (Ubuntu package)
linux-ibm (Ubuntu package)
linux-hwe-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
kernel-64kb
kernel-default-devel-debuginfo
kernel-default-debugsource
kernel-obs-build-debugsource
kernel-obs-build
kernel-syms
kernel-default-devel
kernel-64kb-devel
kernel-64kb-debugsource
kernel-default
linux (Debian package)

How to mitigate CVE-2026-90045

Install security update from vendor's repository.

linux (Ubuntu package) - update to 7.0.0-42.42
linux-oracle (Ubuntu package) - update to 7.0.0-1015.16
linux-gcp (Ubuntu package) - update to 7.0.0-1016.18
linux-aws (Ubuntu package) - update to 7.0.0-1016.17
linux-ibm (Ubuntu package) - update to 7.0.0-1017.17
linux-hwe-7.0 (Ubuntu package) - update to 7.0.0-42.42~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1017.17
kernel-64kb - update to 6.4.0-159998.55.1
kernel-default-devel-debuginfo - update to 6.4.0-159998.55.1
kernel-default-debugsource - update to 6.4.0-159998.55.1
kernel-obs-build-debugsource - update to 6.4.0-159998.55.1
kernel-obs-build - update to 6.4.0-159998.55.1
kernel-syms - update to 6.4.0-159998.55.1
kernel-default-devel - update to 6.4.0-159998.55.1
kernel-64kb-devel - update to 6.4.0-159998.55.1
kernel-64kb-debugsource - update to 6.4.0-159998.55.1
kernel-default - update to 6.4.0-159998.55.1
linux (Debian package) - update to 6.12.111-1

External References

Related Security Bulletins