Skip to content

In the Linux kernel, the following vulnerability has been...

Moderate severity Unreviewed Published Jun 18, 2025 to the GitHub Advisory Database • Updated Nov 14, 2025

Package

No package listed— Suggest a package

Affected versions

Unknown

Patched versions

Unknown

Description

In the Linux kernel, the following vulnerability has been resolved:

fbdev: fb_pm2fb: Avoid potential divide by zero error

In do_fb_ioctl() of fbmem.c, if cmd is FBIOPUT_VSCREENINFO, var will be
copied from user, then go through fb_set_var() and
info->fbops->fb_check_var() which could may be pm2fb_check_var().
Along the path, var->pixclock won't be modified. This function checks
whether reciprocal of var->pixclock is too high. If var->pixclock is
zero, there will be a divide by zero error. So, it is necessary to check
whether denominator is zero to avoid crash. As this bug is found by
Syzkaller, logs are listed below.

divide error in pm2fb_check_var
Call Trace:

fb_set_var+0x367/0xeb0 drivers/video/fbdev/core/fbmem.c:1015
do_fb_ioctl+0x234/0x670 drivers/video/fbdev/core/fbmem.c:1110
fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1189

References

Published by the National Vulnerability Database Jun 18, 2025
Published to the GitHub Advisory Database Jun 18, 2025
Last updated Nov 14, 2025

Severity

Moderate

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Local
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS score

Exploit Prediction Scoring System (EPSS)

This score estimates the probability of this vulnerability being exploited within the next 30 days. Data provided by FIRST.
(2nd percentile)

Weaknesses

Divide By Zero

The product divides a value by zero. Learn more on MITRE.

CVE ID

CVE-2022-49978

GHSA ID

GHSA-2p5r-q4hr-3fg4

Source code

No known source code

Dependabot alerts are not supported on this advisory because it does not have a package from a supported ecosystem with an affected and fixed version.

Learn more about GitHub language support

Loading Checking history
See something to contribute? Suggest improvements for this vulnerability.