CVE-2026-80786: fbdev: Wrap user-invoked calls to fb_set_var() in helper
fbdev: Wrap user-invoked calls to fbsetvar() in helper
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
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linux/Kernelto a version that resolves this vulnerability.Fixed in 6.1.191 - Upgrade
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linux/Kernelto a version that resolves this vulnerability.Fixed in 6.6.160 - Upgrade
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linux/Kernelto a version that resolves this vulnerability.Fixed in 6.12.114 - Upgrade
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linux/Kernelto a version that resolves this vulnerability.Fixed in 6.18.57 - Upgrade
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linux/Kernelto a version that resolves this vulnerability.Fixed in 7.1.11 - Upgrade
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debian/linuxto a version that resolves this vulnerability.Fixed in 7.1.12-1 - Upgrade
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debian/linuxto a version that resolves this vulnerability.Fixed in 7.2.12-1Fixed in 7.2.14-1 - Compensating control
Wrap user-invoked calls to fb_set_var() in a helper that checks with fbcon whether the mode change is possible, updates the hardware state, and then updates fbcon; use the helper for callers in the FBIOPUT_VSCREENINFO ioctl, sysfs, and driver code.
Event History
Frequently Asked Questions
Which interfaces are implicated beyond the existing ioctl path?
The issue concerns mode-change callers in sysfs and driver code. The FBIOPUT_VSCREENINFO ioctl is identified as the only path that already performs all required fbcon-related steps.
What is required to trigger the affected behavior?
A mode change must be initiated through a user-invoked path that reaches fb_set_var(), including the identified sysfs-related callers. The provided information does not specify required privileges or a remote attack vector.
What changes does the fix make?
The fix routes user-invoked fb_set_var() calls through fb_set_var_from_user(), which checks whether fbcon permits the mode change, updates hardware state, and then updates fbcon state. It also updates callers and removes separate fbcon-state handling from ps3fb and sh_mobile_lcdcfb.