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.
Published: 2025-12-08
Score: 7.0 High
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

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Advisories
Source ID Title
Debian DLA Debian DLA DLA-4404-1 linux security update
Debian DLA Debian DLA DLA-4436-1 linux-6.1 security update
Ubuntu USN Ubuntu USN USN-8029-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-8030-1 Linux kernel (GCP) vulnerabilities
Ubuntu USN Ubuntu USN USN-8029-2 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-8048-1 Linux kernel (OEM) vulnerabilities
Ubuntu USN Ubuntu USN USN-8029-3 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-8095-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-8096-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-8095-2 Linux kernel (FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-8096-2 Linux kernel (FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-8100-1 Linux kernel (NVIDIA) vulnerabilities
Ubuntu USN Ubuntu USN USN-8095-3 Linux kernel (Real-time) vulnerabilities
Ubuntu USN Ubuntu USN USN-8096-3 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-8096-4 Linux kernel (Real-time) vulnerabilities
Ubuntu USN Ubuntu USN USN-8095-4 Linux kernel (AWS) vulnerabilities
Ubuntu USN Ubuntu USN USN-8096-5 Linux kernel (NVIDIA Tegra IGX) vulnerabilities
Ubuntu USN Ubuntu USN USN-8116-1 Linux kernel (Intel IoTG Real-time) vulnerabilities
Ubuntu USN Ubuntu USN USN-8125-1 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-8126-1 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-8095-5 Linux kernel (Raspberry Pi) vulnerabilities
Ubuntu USN Ubuntu USN USN-8141-1 Linux kernel (Raspberry Pi) vulnerabilities
Ubuntu USN Ubuntu USN USN-8163-1 Linux kernel (Azure FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-8165-1 Linux kernel (Azure FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-8163-2 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-8243-1 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-8261-1 Linux kernel (Xilinx) vulnerabilities
History

Tue, 09 Dec 2025 12:15:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 7.0, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}

threat_severity

Important


Mon, 08 Dec 2025 01:15:00 +0000

Type Values Removed Values Added
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.
Title fbdev: Add bounds checking in bit_putcs to fix vmalloc-out-of-bounds
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

Subscriptions

Linux Linux Kernel
cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-05-11T21:46:45.832Z

Reserved: 2025-04-16T07:20:57.185Z

Link: CVE-2025-40304

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Deferred

Published: 2025-12-08T01:16:02.567

Modified: 2026-04-15T00:35:42.020

Link: CVE-2025-40304

cve-icon Redhat

Severity : Important

Publid Date: 2025-12-08T00:00:00Z

Links: CVE-2025-40304 - Bugzilla

cve-icon OpenCVE Enrichment

No data.

Weaknesses

No weakness.