Bug 2419870 (CVE-2025-40304) - CVE-2025-40304 kernel: Linux kernel: Out-of-bounds write in fbdev can lead to privilege escalation, information disclosure, or denial of service.
Summary: CVE-2025-40304 kernel: Linux kernel: Out-of-bounds write in fbdev can lead to...
Keywords:
Status: NEW
Alias: CVE-2025-40304
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: 2025-12-08 07:04 UTC by OSIDB Bzimport
Modified: 2026-02-11 17:45 UTC (History)
0 users

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


Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHSA-2026:1727 0 None None None 2026-02-02 15:25:23 UTC
Red Hat Product Errata RHSA-2026:2282 0 None None None 2026-02-09 09:32:00 UTC
Red Hat Product Errata RHSA-2026:2490 0 None None None 2026-02-11 00:16:07 UTC
Red Hat Product Errata RHSA-2026:2535 0 None None None 2026-02-11 11:51:00 UTC
Red Hat Product Errata RHSA-2026:2560 0 None None None 2026-02-11 14:34:08 UTC
Red Hat Product Errata RHSA-2026:2573 0 None None None 2026-02-11 16:30:40 UTC
Red Hat Product Errata RHSA-2026:2577 0 None None None 2026-02-11 17:04:16 UTC
Red Hat Product Errata RHSA-2026:2583 0 None None None 2026-02-11 17:45:05 UTC

Description OSIDB Bzimport 2025-12-08 07:04:51 UTC
In the Linux kernel, the following vulnerability has been resolved:

fbdev: Add bounds checking in bit_putcs to fix vmalloc-out-of-bounds

Add bounds checking to prevent writes past framebuffer boundaries when
rendering text near screen edges. Return early if the Y position is off-screen
and clip image height to screen boundary. Break from the rendering loop if the
X position is off-screen. When clipping image width to fit the screen, update
the character count to match the clipped width to prevent buffer size
mismatches.

Without the character count update, bit_putcs_aligned and bit_putcs_unaligned
receive mismatched parameters where the buffer is allocated for the clipped
width but cnt reflects the original larger count, causing out-of-bounds writes.

Comment 4 errata-xmlrpc 2026-02-02 15:25:22 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10.0 Extended Update Support

Via RHSA-2026:1727 https://access.redhat.com/errata/RHSA-2026:1727

Comment 8 errata-xmlrpc 2026-02-09 09:31:59 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2026:2282 https://access.redhat.com/errata/RHSA-2026:2282

Comment 9 errata-xmlrpc 2026-02-11 00:16:06 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support
  Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions
  Red Hat Enterprise Linux 8.6 Telecommunications Update Service

Via RHSA-2026:2490 https://access.redhat.com/errata/RHSA-2026:2490

Comment 10 errata-xmlrpc 2026-02-11 11:50:57 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions
  Red Hat Enterprise Linux 8.8 Telecommunications Update Service

Via RHSA-2026:2535 https://access.redhat.com/errata/RHSA-2026:2535

Comment 11 errata-xmlrpc 2026-02-11 14:34:05 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

Via RHSA-2026:2560 https://access.redhat.com/errata/RHSA-2026:2560

Comment 12 errata-xmlrpc 2026-02-11 16:30:37 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions

Via RHSA-2026:2573 https://access.redhat.com/errata/RHSA-2026:2573

Comment 13 errata-xmlrpc 2026-02-11 17:04:15 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions

Via RHSA-2026:2577 https://access.redhat.com/errata/RHSA-2026:2577

Comment 14 errata-xmlrpc 2026-02-11 17:45:04 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

Via RHSA-2026:2583 https://access.redhat.com/errata/RHSA-2026:2583


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