CVE-2026-98201

Received Received - Intake

BaseFortify

Publication date: 2026-10-06

Last updated on: 2026-10-19

Assigner: kernel.org

Description

In the Linux kernel, the following vulnerability has been resolved: Input: zero ff_effect before compat copy in input_ff_effect_from_user In the compat path input_ff_effect_from_user() aliases the caller's native struct ff_effect with the smaller struct ff_effect_compat and copies only the compat sized prefix: compat_effect = (struct ff_effect_compat *)effect; if (copy_from_user(compat_effect, buffer, sizeof(struct ff_effect_compat))) The tail of the native structure is never written. Callers pass an uninitialized on-stack object, for example evdev_do_ioctl() for EVIOCSFF, so those bytes keep their previous stack contents. input_ff_upload() then stores the full native structure in ff->effects[id], from where a uinput based force feedback daemon can read it back via UI_BEGIN_FF_UPLOAD, disclosing kernel stack memory to userspace. Zero the effect before the compat copy.

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-10-06

Last Modified

2026-10-19

Generated

2026-10-19

AI Q&A

2026-10-06

EPSS Evaluated

2026-10-18

NVD

CVE-2026-98201

EUVD

EUVD-2026-93129

Affected Vendors & Products

Vendor	Product	Version / Range
Linux	Linux	2d56f3a32c0e62f99c043d2579840f9731fe5855
Linux	Linux	2d56f3a32c0e62f99c043d2579840f9731fe5855
Linux	Linux	2d56f3a32c0e62f99c043d2579840f9731fe5855
Linux	Linux	2d56f3a32c0e62f99c043d2579840f9731fe5855
Linux	Linux	2d56f3a32c0e62f99c043d2579840f9731fe5855
Linux	Linux	2d56f3a32c0e62f99c043d2579840f9731fe5855
Linux	Linux	2d56f3a32c0e62f99c043d2579840f9731fe5855
Linux	Linux	2d56f3a32c0e62f99c043d2579840f9731fe5855
Linux	Linux	2.6.29

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-UNKNOWN

Attack-Flow Graph

Executive Summary

This vulnerability in the Linux kernel involves a memory disclosure issue in the input subsystem. When handling force feedback effects, the kernel copies a smaller structure to userspace but leaves uninitialized memory in the original structure. This uninitialized memory, containing previous stack contents, can later be read by a force feedback daemon, exposing sensitive kernel stack data to userspace.

Detection Guidance

This vulnerability is specific to the Linux kernel's input subsystem and does not have network-based detection methods. To detect it, check if your Linux kernel version is vulnerable by running: uname -a. If your kernel version is below the patched version, the system is likely vulnerable.

Impact Analysis

This vulnerability could allow local users to read kernel stack memory, potentially exposing sensitive information such as passwords, encryption keys, or other secrets that were previously stored on the stack. It may also be used to aid in further exploitation of kernel vulnerabilities.

Compliance Impact

This vulnerability allows disclosure of kernel stack memory to userspace, which could potentially expose sensitive data. While not directly tied to GDPR or HIPAA, such memory leaks may violate data protection principles under GDPR if personal data is exposed. HIPAA compliance could be impacted if protected health information is leaked through this flaw.

Mitigation Strategies

Update your Linux kernel to the latest patched version immediately. If updating is not immediately possible, restrict access to /dev/uinput and related input devices to trusted users only to limit exposure.

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