In the Linux kernel, the following vulnerability has been resolved: fbdev: Fix fb_new_modelist to prevent null-ptr-deref in fb_videomode_to_var… (CVE-2026-53403)
A vulnerability in the Linux kernel framebuffer subsystem (fbdev) was resolved that could lead to a null pointer dereference. The issue arises when the framebuffer's current mode (info->var) no longer matches any mode in the mode list (info->modelist) after userspace replaces the mode list. This mismatch can cause a null pointer dereference in fb_videomode_to_var() during console operations when fbcon is unbound. The fix ensures the current mode remains in the mode list to prevent this condition.
AI Analysis
Technical Summary
The Linux kernel framebuffer subsystem had a flaw in fb_new_modelist() where replacing the mode list from userspace could leave the current mode (info->var) unmatched in the mode list (info->modelist). This leads to fb_match_mode() returning NULL, causing fb_videomode_to_var() to dereference a NULL pointer during console takeover operations when fbcon is unbound. The patch keeps the current mode in the mode list, preventing the null pointer dereference.
Potential Impact
This vulnerability can cause a kernel null pointer dereference, which may lead to a kernel crash (panic) or denial of service. There is no indication of code execution or privilege escalation from the provided data.
Mitigation Recommendations
A fix has been implemented in the Linux kernel to keep the current framebuffer mode in the mode list, preventing the null pointer dereference. Users should update their Linux kernel to a version that includes this fix once it is released. Patch status is not yet confirmed in the provided data; check the official Linux kernel advisories or vendor updates for the exact fixed versions and patch availability.
In the Linux kernel, the following vulnerability has been resolved: fbdev: Fix fb_new_modelist to prevent null-ptr-deref in fb_videomode_to_var… (CVE-2026-53403)
Description
A vulnerability in the Linux kernel framebuffer subsystem (fbdev) was resolved that could lead to a null pointer dereference. The issue arises when the framebuffer's current mode (info->var) no longer matches any mode in the mode list (info->modelist) after userspace replaces the mode list. This mismatch can cause a null pointer dereference in fb_videomode_to_var() during console operations when fbcon is unbound. The fix ensures the current mode remains in the mode list to prevent this condition.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The Linux kernel framebuffer subsystem had a flaw in fb_new_modelist() where replacing the mode list from userspace could leave the current mode (info->var) unmatched in the mode list (info->modelist). This leads to fb_match_mode() returning NULL, causing fb_videomode_to_var() to dereference a NULL pointer during console takeover operations when fbcon is unbound. The patch keeps the current mode in the mode list, preventing the null pointer dereference.
Potential Impact
This vulnerability can cause a kernel null pointer dereference, which may lead to a kernel crash (panic) or denial of service. There is no indication of code execution or privilege escalation from the provided data.
Mitigation Recommendations
A fix has been implemented in the Linux kernel to keep the current framebuffer mode in the mode list, preventing the null pointer dereference. Users should update their Linux kernel to a version that includes this fix once it is released. Patch status is not yet confirmed in the provided data; check the official Linux kernel advisories or vendor updates for the exact fixed versions and patch availability.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-mppp-59pm-fqxw
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-53403"]
- Ecosystems
- []
- Database Specific Severity
- null
- Cvss Version
- null
Threat ID: 6a5d27ad2a4a8d59891318c5
Added to database: 07/19/2026, 19:38:21 UTC
Last enriched: 07/19/2026, 20:20:07 UTC
Last updated: 07/20/2026, 17:26:47 UTC
Views: 11
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