{"id":"CVE-2026-64271","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-64271","summary":"Input: touchwin - reset the packet index on every complete packet","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nInput: touchwin - reset the packet index on every complete packet\n\ntw_interrupt() accumulates each non-zero serial byte into a fixed\nthree-byte buffer with a running index that is only reset once a full\npacket has been received *and* the device's two Y bytes agree:\n\n\ttw->data[tw->idx++] = data;\n\tif (tw->idx == TW_LENGTH && tw->data[1] == tw->data[2]) {\n\t\t...\n\t\ttw->idx = 0;\n\t}\n\nThe reset is gated on tw->data[1] == tw->data[2], a value the device\ncontrols.  A malicious, malfunctioning or counterfeit Touchwindow\nperipheral can stream non-zero bytes whose 2nd and 3rd bytes differ: the\nindex reaches TW_LENGTH without the equality holding, is never reset, and\nkeeps growing, so tw->data[tw->idx++] walks off the end of the three-byte\narray and the rest of the heap-allocated struct tw, one attacker-chosen\nbyte at a time -- an unbounded, device-driven heap out-of-bounds write.\n\nReset the index on every completed packet and report an event only when\nthe two Y bytes match, like the other serio touchscreen drivers do.","published":"2026-07-25T08:49:18.160Z","modified":"2026-08-12T03:51:08.170074696Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Linux","name":"Kernel","fixedVersion":"5.10.261"}],"fix":null,"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/044167cba2384bcd783547ad5e30ecd292b30919"},{"type":"WEB","url":"https://git.kernel.org/stable/c/3e6f007b43e2fc6546e21fa74ee62c38984a6672"},{"type":"WEB","url":"https://git.kernel.org/stable/c/431ad239f2924dff337c3fccb9246597c1b63185"},{"type":"WEB","url":"https://git.kernel.org/stable/c/478cdd736f2ce3114f90e775d7358136d3977b94"},{"type":"WEB","url":"https://git.kernel.org/stable/c/6c9f29f128dd4057404838259af4c645318487e1"},{"type":"WEB","url":"https://git.kernel.org/stable/c/70e4248793762df9832fd4fc2fc6ac7924572c36"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a8d87184576c889759e3aab899799a482f1e1a5b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ed9b66905407eb3d02df1aaeed82eb7a7f0eb508"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64271.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64271"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:08.170074696Z"}}