{"id":"CVE-2022-50131","state":"PUBLISHED","title":"HID: mcp2221: prevent a buffer overflow in mcp_smbus_write()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nHID: mcp2221: prevent a buffer overflow in mcp_smbus_write()\n\nSmatch Warning:\ndrivers/hid/hid-mcp2221.c:388 mcp_smbus_write() error: __memcpy()\n'&mcp->txbuf[5]' too small (59 vs 255)\ndrivers/hid/hid-mcp2221.c:388 mcp_smbus_write() error: __memcpy() 'buf'\ntoo small (34 vs 255)\n\nThe 'len' variable can take a value between 0-255 as it can come from\ndata->block[0] and it is user data. So add an bound check to prevent a\nbuffer overflow in memcpy().","publishedAt":"2025-06-18T11:02:56.796Z","updatedAt":"2026-08-05T08:57:29.234Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"67a95c21463d066060b0f66d65a75d45bb386ffb","status":"affected","lessThan":"66c8e816f2f2ca4a61b406503bd10bad1b35f72f","versionType":"git"},{"version":"67a95c21463d066060b0f66d65a75d45bb386ffb","status":"affected","lessThan":"91443c669d280937968f0aa4edefa741cfe35314","versionType":"git"},{"version":"67a95c21463d066060b0f66d65a75d45bb386ffb","status":"affected","lessThan":"6402116a7b5ec80fa40fd145a80c813019cd555f","versionType":"git"},{"version":"67a95c21463d066060b0f66d65a75d45bb386ffb","status":"affected","lessThan":"3c0f8a59f2cc8841ee6653399a77f4f3e6e9a270","versionType":"git"},{"version":"67a95c21463d066060b0f66d65a75d45bb386ffb","status":"affected","lessThan":"62ac2473553a00229e67bdf3cb023b62cf7f5a9a","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/hid/hid-mcp2221.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.7","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.7","versionType":"semver"},{"version":"5.10.137","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.61","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"5.18.18","status":"unaffected","lessThanOrEqual":"5.18.*","versionType":"semver"},{"version":"5.19.2","status":"unaffected","lessThanOrEqual":"5.19.*","versionType":"semver"},{"version":"6.0","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-mcp2221.c"]}],"references":["https://git.kernel.org/stable/c/66c8e816f2f2ca4a61b406503bd10bad1b35f72f","https://git.kernel.org/stable/c/91443c669d280937968f0aa4edefa741cfe35314","https://git.kernel.org/stable/c/6402116a7b5ec80fa40fd145a80c813019cd555f","https://git.kernel.org/stable/c/3c0f8a59f2cc8841ee6653399a77f4f3e6e9a270","https://git.kernel.org/stable/c/62ac2473553a00229e67bdf3cb023b62cf7f5a9a"],"weaknesses":[],"ingestedAt":"2026-10-29T20:05:26.763Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2022/50xxx/CVE-2022-50131.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2022-50131","state":"PUBLISHED","datePublished":"2025-06-18T11:02:56.796Z","dateUpdated":"2026-08-05T08:57:29.234Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2025-06-18T10:57:27.418Z"},"containers":{"cna":{"title":"HID: mcp2221: prevent a buffer overflow in mcp_smbus_write()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nHID: mcp2221: prevent a buffer overflow in mcp_smbus_write()\n\nSmatch Warning:\ndrivers/hid/hid-mcp2221.c:388 mcp_smbus_write() error: __memcpy()\n'&mcp->txbuf[5]' too small (59 vs 255)\ndrivers/hid/hid-mcp2221.c:388 mcp_smbus_write() error: __memcpy() 'buf'\ntoo small (34 vs 255)\n\nThe 'len' variable can take a value between 0-255 as it can come from\ndata->block[0] and it is user data. So add an bound check to prevent a\nbuffer overflow in memcpy()."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"67a95c21463d066060b0f66d65a75d45bb386ffb","status":"affected","lessThan":"66c8e816f2f2ca4a61b406503bd10bad1b35f72f","versionType":"git"},{"version":"67a95c21463d066060b0f66d65a75d45bb386ffb","status":"affected","lessThan":"91443c669d280937968f0aa4edefa741cfe35314","versionType":"git"},{"version":"67a95c21463d066060b0f66d65a75d45bb386ffb","status":"affected","lessThan":"6402116a7b5ec80fa40fd145a80c813019cd555f","versionType":"git"},{"version":"67a95c21463d066060b0f66d65a75d45bb386ffb","status":"affected","lessThan":"3c0f8a59f2cc8841ee6653399a77f4f3e6e9a270","versionType":"git"},{"version":"67a95c21463d066060b0f66d65a75d45bb386ffb","status":"affected","lessThan":"62ac2473553a00229e67bdf3cb023b62cf7f5a9a","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/hid/hid-mcp2221.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.7","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.7","versionType":"semver"},{"version":"5.10.137","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.61","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"5.18.18","status":"unaffected","lessThanOrEqual":"5.18.*","versionType":"semver"},{"version":"5.19.2","status":"unaffected","lessThanOrEqual":"5.19.*","versionType":"semver"},{"version":"6.0","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-mcp2221.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/66c8e816f2f2ca4a61b406503bd10bad1b35f72f"},{"url":"https://git.kernel.org/stable/c/91443c669d280937968f0aa4edefa741cfe35314"},{"url":"https://git.kernel.org/stable/c/6402116a7b5ec80fa40fd145a80c813019cd555f"},{"url":"https://git.kernel.org/stable/c/3c0f8a59f2cc8841ee6653399a77f4f3e6e9a270"},{"url":"https://git.kernel.org/stable/c/62ac2473553a00229e67bdf3cb023b62cf7f5a9a"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The overflow is reached via the local i2c-dev I2C_SMBUS ioctl into mcp_smbus_xfer()/mcp_smbus_write(), not by crafted USB HID reports. An attached MCP2221 is a deployment precondition; the attack is a local syscall against /dev/i2c-N.\nAC:L - An attacker who can open the adapter sets data->block[0] above I2C_SMBUS_BLOCK_MAX and triggers memcpy into txbuf[64] on the write path before any USB/I2C slave response, so no race or external state is required.\nPR:L - i2cdev_open() has no capability check; access depends on /dev/i2c-* permissions (commonly 0660 root:i2c or equivalent on embedded/industrial systems), which is basic local access rather than real root.\nUI:N - Exploitation needs only ioctl(I2C_SMBUS) with an oversized block write (I2C_SMBUS_BLOCK_DATA / I2C_SMBUS_I2C_BLOCK_DATA / BLOCK_PROC_CALL); no victim interaction is required.\nS:U - This is ordinary host-kernel heap memory corruption (local privilege escalation/DoS) with no VM escape, IOMMU bypass, or other cross-authority impact.\nC:H - Oversized memcpy into mcp->txbuf overflows the heap-allocated struct mcp2221 and adjacent heap, a memory-corruption primitive that can be leveraged for information disclosure.\nI:H - Out-of-bounds heap write of up to ~196 bytes past txbuf (controlled length from data->block[0]) can corrupt adjacent state including pointers (e.g. gc) and enable integrity compromise/control-flow hijacking.\nA:H - The same heap corruption can oops or panic the kernel even when not fully exploited for code execution."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T08:57:29.234Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"5.10.137"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"5.15.61"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"5.18.18"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"5.19.2"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"6.0"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}