{"id":"CVE-2026-89628","state":"PUBLISHED","title":"HID: picolcd: clamp eeprom debugfs read to bytes actually received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nHID: picolcd: clamp eeprom debugfs read to bytes actually received\n\npicolcd_debug_eeprom_read() trusts resp->raw_data[2] -- a length byte\nsupplied by the device in its REPORT_EE_DATA reply -- clamped only to\nthe caller's read() count:\n\n\tret = resp->raw_data[2];\n\tif (ret > s)\n\t\tret = s;\n\tif (copy_to_user(u, resp->raw_data+3, ret))\n\nIt never checks resp->raw_size, the number of bytes picolcd_raw_event()\nactually copied into the 64-byte raw_data[] of the kmalloc'd struct\npicolcd_pending. A device (or a spoofed picoLCD) returning a length byte\nof 0xff, read with a count >= 255, makes copy_to_user() read past\nraw_data[] into adjacent slab memory and return it to userspace through\nthe debugfs \"eeprom\" file:\n\n\tBUG: KASAN: slab-out-of-bounds in _copy_to_user\n\tRead of size 255 ... picolcd_debug_eeprom_read+0x214/0x2f0 [hid_picolcd]\n\nThe debug-dump path in the same file already validates the device length\nbyte against the received size before trusting it; this read does not.\nThe file is created S_IRUSR (root-only) and a crafted device is needed,\nso it is neither unprivileged- nor remotely-triggerable.\n\nClamp the copy length to resp->raw_size - 3 (the payload actually\nreceived, minus the 3-byte header), floored at 0 for short replies.","publishedAt":"2026-09-11T19:45:24.203Z","updatedAt":"2026-10-19T08:50:00.490Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"9bbf2b98ba11d00bd73e3254e15cfe17ccaff6ba","status":"affected","lessThan":"1a02056c2bf7ef9b5fd05ee6913aeeadb703c443","versionType":"git"},{"version":"9bbf2b98ba11d00bd73e3254e15cfe17ccaff6ba","status":"affected","lessThan":"65daa322f1021d8206f8032c4cd4c0cb2d26c7c3","versionType":"git"},{"version":"9bbf2b98ba11d00bd73e3254e15cfe17ccaff6ba","status":"affected","lessThan":"8dc662af019158690c470edd2e2857657f700abb","versionType":"git"},{"version":"9bbf2b98ba11d00bd73e3254e15cfe17ccaff6ba","status":"affected","lessThan":"4daf432c94a42e7be6aa10b012b33af5ed9bc118","versionType":"git"},{"version":"9bbf2b98ba11d00bd73e3254e15cfe17ccaff6ba","status":"affected","lessThan":"a3e6e8d7198a9f3861861520a38b673684a1062b","versionType":"git"},{"version":"9bbf2b98ba11d00bd73e3254e15cfe17ccaff6ba","status":"affected","lessThan":"471f4a939c66d1d44aece2321807abf609fc9098","versionType":"git"},{"version":"9bbf2b98ba11d00bd73e3254e15cfe17ccaff6ba","status":"affected","lessThan":"699a3c8b56e168ca19d12722f3f5ef1d6f4b1d84","versionType":"git"},{"version":"9bbf2b98ba11d00bd73e3254e15cfe17ccaff6ba","status":"affected","lessThan":"e9c667395ac1f8024f623250b32bae4c7af9caa0","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/hid/hid-picolcd_debugfs.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.35","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.35","versionType":"semver"},{"version":"5.10.270","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.221","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.188","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.109","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.50","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.4","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/hid/hid-picolcd_debugfs.c"]}],"references":["https://git.kernel.org/stable/c/1a02056c2bf7ef9b5fd05ee6913aeeadb703c443","https://git.kernel.org/stable/c/65daa322f1021d8206f8032c4cd4c0cb2d26c7c3","https://git.kernel.org/stable/c/8dc662af019158690c470edd2e2857657f700abb","https://git.kernel.org/stable/c/4daf432c94a42e7be6aa10b012b33af5ed9bc118","https://git.kernel.org/stable/c/a3e6e8d7198a9f3861861520a38b673684a1062b","https://git.kernel.org/stable/c/471f4a939c66d1d44aece2321807abf609fc9098","https://git.kernel.org/stable/c/699a3c8b56e168ca19d12722f3f5ef1d6f4b1d84","https://git.kernel.org/stable/c/e9c667395ac1f8024f623250b32bae4c7af9caa0"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:26.108Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/89xxx/CVE-2026-89628.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-89628","state":"PUBLISHED","datePublished":"2026-09-11T19:45:24.203Z","dateUpdated":"2026-10-19T08:50:00.490Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-11T19:38:34.738Z"},"containers":{"cna":{"title":"HID: picolcd: clamp eeprom debugfs read to bytes actually received","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nHID: picolcd: clamp eeprom debugfs read to bytes actually received\n\npicolcd_debug_eeprom_read() trusts resp->raw_data[2] -- a length byte\nsupplied by the device in its REPORT_EE_DATA reply -- clamped only to\nthe caller's read() count:\n\n\tret = resp->raw_data[2];\n\tif (ret > s)\n\t\tret = s;\n\tif (copy_to_user(u, resp->raw_data+3, ret))\n\nIt never checks resp->raw_size, the number of bytes picolcd_raw_event()\nactually copied into the 64-byte raw_data[] of the kmalloc'd struct\npicolcd_pending. A device (or a spoofed picoLCD) returning a length byte\nof 0xff, read with a count >= 255, makes copy_to_user() read past\nraw_data[] into adjacent slab memory and return it to userspace through\nthe debugfs \"eeprom\" file:\n\n\tBUG: KASAN: slab-out-of-bounds in _copy_to_user\n\tRead of size 255 ... picolcd_debug_eeprom_read+0x214/0x2f0 [hid_picolcd]\n\nThe debug-dump path in the same file already validates the device length\nbyte against the received size before trusting it; this read does not.\nThe file is created S_IRUSR (root-only) and a crafted device is needed,\nso it is neither unprivileged- nor remotely-triggerable.\n\nClamp the copy length to resp->raw_size - 3 (the payload actually\nreceived, minus the 3-byte header), floored at 0 for short replies."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"9bbf2b98ba11d00bd73e3254e15cfe17ccaff6ba","status":"affected","lessThan":"1a02056c2bf7ef9b5fd05ee6913aeeadb703c443","versionType":"git"},{"version":"9bbf2b98ba11d00bd73e3254e15cfe17ccaff6ba","status":"affected","lessThan":"65daa322f1021d8206f8032c4cd4c0cb2d26c7c3","versionType":"git"},{"version":"9bbf2b98ba11d00bd73e3254e15cfe17ccaff6ba","status":"affected","lessThan":"8dc662af019158690c470edd2e2857657f700abb","versionType":"git"},{"version":"9bbf2b98ba11d00bd73e3254e15cfe17ccaff6ba","status":"affected","lessThan":"4daf432c94a42e7be6aa10b012b33af5ed9bc118","versionType":"git"},{"version":"9bbf2b98ba11d00bd73e3254e15cfe17ccaff6ba","status":"affected","lessThan":"a3e6e8d7198a9f3861861520a38b673684a1062b","versionType":"git"},{"version":"9bbf2b98ba11d00bd73e3254e15cfe17ccaff6ba","status":"affected","lessThan":"471f4a939c66d1d44aece2321807abf609fc9098","versionType":"git"},{"version":"9bbf2b98ba11d00bd73e3254e15cfe17ccaff6ba","status":"affected","lessThan":"699a3c8b56e168ca19d12722f3f5ef1d6f4b1d84","versionType":"git"},{"version":"9bbf2b98ba11d00bd73e3254e15cfe17ccaff6ba","status":"affected","lessThan":"e9c667395ac1f8024f623250b32bae4c7af9caa0","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/hid/hid-picolcd_debugfs.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.35","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.35","versionType":"semver"},{"version":"5.10.270","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.221","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.188","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.109","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.50","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.4","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/hid/hid-picolcd_debugfs.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/1a02056c2bf7ef9b5fd05ee6913aeeadb703c443"},{"url":"https://git.kernel.org/stable/c/65daa322f1021d8206f8032c4cd4c0cb2d26c7c3"},{"url":"https://git.kernel.org/stable/c/8dc662af019158690c470edd2e2857657f700abb"},{"url":"https://git.kernel.org/stable/c/4daf432c94a42e7be6aa10b012b33af5ed9bc118"},{"url":"https://git.kernel.org/stable/c/a3e6e8d7198a9f3861861520a38b673684a1062b"},{"url":"https://git.kernel.org/stable/c/471f4a939c66d1d44aece2321807abf609fc9098"},{"url":"https://git.kernel.org/stable/c/699a3c8b56e168ca19d12722f3f5ef1d6f4b1d84"},{"url":"https://git.kernel.org/stable/c/e9c667395ac1f8024f623250b32bae4c7af9caa0"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T08:50:00.490Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.35","versionEndExcluding":"5.10.270"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.35","versionEndExcluding":"5.15.221"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.35","versionEndExcluding":"6.1.188"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.35","versionEndExcluding":"6.6.157"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.35","versionEndExcluding":"6.12.109"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.35","versionEndExcluding":"6.18.50"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.35","versionEndExcluding":"7.2.4"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.35","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}