{"id":"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-\u003edata[tw-\u003eidx++] = data;\n\tif (tw-\u003eidx == TW_LENGTH && tw-\u003edata[1] == tw-\u003edata[2]) {\n\t\t...\n\t\ttw-\u003eidx = 0;\n\t}\n\nThe reset is gated on tw-\u003edata[1] == tw-\u003edata[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-\u003edata[tw-\u003eidx++] 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.","modified":"2026-08-18T03:30:50.075707027Z","published":"2026-07-25T08:49:18.160Z","related":["openSUSE-SU-2026:11476-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64271.json"},"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"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"11ea3173d5f2de71d037ef58ac43395795fed2bc"},{"fixed":"ed9b66905407eb3d02df1aaeed82eb7a7f0eb508"},{"fixed":"044167cba2384bcd783547ad5e30ecd292b30919"},{"fixed":"6c9f29f128dd4057404838259af4c645318487e1"},{"fixed":"431ad239f2924dff337c3fccb9246597c1b63185"},{"fixed":"70e4248793762df9832fd4fc2fc6ac7924572c36"},{"fixed":"3e6f007b43e2fc6546e21fa74ee62c38984a6672"},{"fixed":"a8d87184576c889759e3aab899799a482f1e1a5b"},{"fixed":"478cdd736f2ce3114f90e775d7358136d3977b94"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64271.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.6.19"},{"fixed":"5.10.261"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.212"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.178"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.145"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.96"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.39"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.4"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64271.json"}}],"schema_version":"1.9.0"}