CVE-2026-80580
In the Linux kernel, the following vulnerability has been resolved:
fbdev: bound mode sysfs output to the sysfs buffer
mode_string() uses snprintf() which can return a value larger than the
remaining buffer space. show_modes() accumulates the return value into i
without checking whether i has reached PAGE_SIZE, causing the offset to
advance past the sysfs buffer if the modelist is long enough.
Add a size parameter to mode_string() and use scnprintf() to return
only the bytes actually written. Add an early return when offset
already exceeds the buffer. In show_modes(), stop accumulating once
the buffer is full.
CSIRTS triage
- What
- fbdev sysfs mode output is not bounded to the sysfs buffer, allowing buffer overread.
- Who is affected
- Systems using fbdev with sysfs interface exposed; typically local access required.
- Urgency
- Low priority; bounded disclosure with limited exploitability.
- Action
- Apply patch limiting fbdev mode sysfs output to sysfs buffer size.
AI-assisted analysis generated from the source advisory — verify against the original.
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Exploitation outlook
- Low exploitation risk0.11% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 2% of all EPSS-scored CVEs.
Advisory coverage (2)
External references
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