CVE-2026-64271EPSS p5.6%
CVE-2026-64271CVE-2026-64271
linux / linux_kernel
Description
In the Linux kernel, the following vulnerability has been resolved:
Input: touchwin - reset the packet index on every complete packet
tw_interrupt() accumulates each non-zero serial byte into a fixed
three-byte buffer with a running index that is only reset once a full
packet has been received *and* the device's two Y bytes agree:
tw->data[tw->idx++] = data;
if (tw->idx == TW_LENGTH && tw->data[1] == tw->data[2]) {
...
tw->idx = 0;
}
The reset is gated on tw->data[1] == tw->data[2], a value the device
controls. A malicious, malfunctioning or counterfeit Touchwindow
peripheral can stream non-zero bytes whose 2nd and 3rd bytes differ: the
index reaches TW_LENGTH without the equality holding, is never reset, and
keeps growing, so tw->data[tw->idx++] walks off the end of the three-byte
array and the rest of the heap-allocated struct tw, one attacker-chosen
byte at a time -- an unbounded, device-driven heap out-of-bounds write.
Reset the index on every completed packet and repo
Scoring
| CVSS | 7.8 () |
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| EPSS | 0.17% probability of exploitation · percentile 5.6% · 2026-10-05T12:00:23Z |
| Last modified | 2026-08-17 |