CVE-2026-89751EPSS p6.0%
CVE-2026-89751CVE-2026-89751
Description
In the Linux kernel, the following vulnerability has been resolved:
x86/tdx: Fix off-by-one in port I/O handling
handle_in() and handle_out() in arch/x86/coco/tdx/tdx.c use:
u64 mask = GENMASK(BITS_PER_BYTE * size, 0);
GENMASK(h, l) includes bit h. For size=1 (INB), this produces
GENMASK(8, 0) = 0x1FF (9 bits) instead of GENMASK(7, 0) = 0xFF (8
bits). The mask is one bit too wide for all I/O sizes.
Fix the mask calculation.
Scoring
| EPSS | 0.17% probability of exploitation · percentile 6.0% · 2026-10-05T12:00:23Z |
| Last modified | 2026-09-14 |