CVE-2025-40304
Description
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.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or โ if you've already worked around this in production โ publish your fix to the community-verified tier.
โ Propose a mitigation on Community โ Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
SUSE Affected 1 release
| Version | Status | Fixed in |
|---|---|---|
| โ | Affected | โ |
AlmaLinux Fixed 1 release
| Version | Status | Fixed in |
|---|---|---|
| 9 | Fixed | kernel-64k-devel-matched-5.14.0-611.34.1.el9_7.aarch64.rpm |
Debian Fixed 5 releases
| Version | Status | Fixed in |
|---|---|---|
| trixie | Fixed | 6.12.63-1 |
| sid | Fixed | 6.17.8-1 |
| forky | Fixed | 6.17.8-1 |
| bullseye | Fixed | 5.10.247-1 |
| bookworm | Fixed | 6.1.159-1 |
Red Hat Fixed 2 releases
| Version | Status | Fixed in |
|---|---|---|
| 9 | Fixed | โ |
| 8 | Fixed | โ |
Rocky Linux Fixed 2 releases
| Version | Status | Fixed in |
|---|---|---|
| 9 | Fixed | โ |
| 8 | Fixed | โ |
References
- https://errata.rockylinux.org/RLSA-2026:2821
- https://errata.rockylinux.org/RLSA-2026:2720
- https://access.redhat.com/errata/RHSA-2026:2722
- https://www.suse.com/security/cve/CVE-2025-40304.html
- https://errata.rockylinux.org/RLSA-2026:2722
- https://security-tracker.debian.org/tracker/CVE-2025-40304
- https://access.redhat.com/errata/RHSA-2026:2720
- https://bugzilla.redhat.com/2414482
- https://bugzilla.redhat.com/2419838
- https://bugzilla.redhat.com/2419870
- https://errata.almalinux.org/8/ALSA-2026-2720.html
- https://access.redhat.com/errata/RHSA-2026:2821
- https://errata.almalinux.org/8/ALSA-2026-2821.html
- https://bugzilla.redhat.com/2360239
- https://bugzilla.redhat.com/2406747
- https://bugzilla.redhat.com/2419902
- https://bugzilla.redhat.com/2424880
- https://bugzilla.redhat.com/2429116
- https://bugzilla.redhat.com/2432671
- https://errata.almalinux.org/9/ALSA-2026-2722.html
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.