Bug 2521381 (CVE-2026-74673) - CVE-2026-74673 kernel: Input: evdev - fix information leak in evdev_pass_values()
Summary: CVE-2026-74673 kernel: Input: evdev - fix information leak in evdev_pass_valu...
Keywords:
Status: NEW
Alias: CVE-2026-74673
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Product Security DevOps Team
QA Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-08-22 15:42 UTC by OSIDB Bzimport
Modified: 2026-08-24 09:55 UTC (History)
2 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed:
Embargoed:


Attachments (Terms of Use)

Description OSIDB Bzimport 2026-08-22 15:42:44 UTC
In the Linux kernel, the following vulnerability has been resolved:

Input: evdev - fix information leak in evdev_pass_values()

In evdev_pass_values(), the input_event structure is allocated on the
kernel stack and populated field-by-field. However, it is never fully
initialized. On architectures where struct input_event contains explicit
or implicit padding (such as the 32-bit __pad field on SPARC64), these
padding bytes are left uninitialized.

When this event structure is subsequently passed to the client buffer
and later copied to userspace, the uninitialized padding bytes leak
kernel stack memory, potentially exposing sensitive information.

Similar issues exist in __evdev_queue_syn_dropped and __pass_event.

Fix this by explicitly zeroing the entire event structure with memset()
before populating its fields. This ensures all padding bytes are cleared
before the data crosses the security boundary.


Note You need to log in before you can comment on or make changes to this bug.