{"id":"CVE-2026-31401","state":"PUBLISHED","title":"HID: bpf: prevent buffer overflow in hid_hw_request","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nHID: bpf: prevent buffer overflow in hid_hw_request\n\nright now the returned value is considered to be always valid. However,\nwhen playing with HID-BPF, the return value can be arbitrary big,\nbecause it's the return value of dispatch_hid_bpf_raw_requests(), which\ncalls the struct_ops and we have no guarantees that the value makes\nsense.","publishedAt":"2026-04-03T15:16:04.903Z","updatedAt":"2026-10-19T18:35:46.408Z","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":"8bd0488b5ea58655ad6fdcbe0408ef49b16882b1","status":"affected","lessThan":"d6efaa50af62fb0790dd1fd4e7e5506b46312510","versionType":"git"},{"version":"8bd0488b5ea58655ad6fdcbe0408ef49b16882b1","status":"affected","lessThan":"73c5b5aea1c443239c8cb4191b4af7a4bd6fd7b1","versionType":"git"},{"version":"8bd0488b5ea58655ad6fdcbe0408ef49b16882b1","status":"affected","lessThan":"eb57dae20fdf6f3069cdc07821fa3bb46de381d7","versionType":"git"},{"version":"8bd0488b5ea58655ad6fdcbe0408ef49b16882b1","status":"affected","lessThan":"2b658c1c442ec1cd9eec5ead98d68662c40fe645","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/hid/bpf/hid_bpf_dispatch.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.11","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.11","versionType":"semver"},{"version":"6.12.78","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.20","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.10","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/hid/bpf/hid_bpf_dispatch.c"]}],"references":["https://git.kernel.org/stable/c/d6efaa50af62fb0790dd1fd4e7e5506b46312510","https://git.kernel.org/stable/c/73c5b5aea1c443239c8cb4191b4af7a4bd6fd7b1","https://git.kernel.org/stable/c/eb57dae20fdf6f3069cdc07821fa3bb46de381d7","https://git.kernel.org/stable/c/2b658c1c442ec1cd9eec5ead98d68662c40fe645"],"weaknesses":["CWE-120"],"ingestedAt":"2026-10-29T20:11:40.391Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/31xxx/CVE-2026-31401.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-31401","state":"PUBLISHED","datePublished":"2026-04-03T15:16:04.903Z","dateUpdated":"2026-10-19T18:35:46.408Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-03-09T15:48:24.086Z"},"containers":{"cna":{"title":"HID: bpf: prevent buffer overflow in hid_hw_request","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nHID: bpf: prevent buffer overflow in hid_hw_request\n\nright now the returned value is considered to be always valid. However,\nwhen playing with HID-BPF, the return value can be arbitrary big,\nbecause it's the return value of dispatch_hid_bpf_raw_requests(), which\ncalls the struct_ops and we have no guarantees that the value makes\nsense."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"8bd0488b5ea58655ad6fdcbe0408ef49b16882b1","status":"affected","lessThan":"d6efaa50af62fb0790dd1fd4e7e5506b46312510","versionType":"git"},{"version":"8bd0488b5ea58655ad6fdcbe0408ef49b16882b1","status":"affected","lessThan":"73c5b5aea1c443239c8cb4191b4af7a4bd6fd7b1","versionType":"git"},{"version":"8bd0488b5ea58655ad6fdcbe0408ef49b16882b1","status":"affected","lessThan":"eb57dae20fdf6f3069cdc07821fa3bb46de381d7","versionType":"git"},{"version":"8bd0488b5ea58655ad6fdcbe0408ef49b16882b1","status":"affected","lessThan":"2b658c1c442ec1cd9eec5ead98d68662c40fe645","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/hid/bpf/hid_bpf_dispatch.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.11","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.11","versionType":"semver"},{"version":"6.12.78","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.20","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.10","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/hid/bpf/hid_bpf_dispatch.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/d6efaa50af62fb0790dd1fd4e7e5506b46312510"},{"url":"https://git.kernel.org/stable/c/73c5b5aea1c443239c8cb4191b4af7a4bd6fd7b1"},{"url":"https://git.kernel.org/stable/c/eb57dae20fdf6f3069cdc07821fa3bb46de381d7"},{"url":"https://git.kernel.org/stable/c/2b658c1c442ec1cd9eec5ead98d68662c40fe645"}],"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 vulnerable `memcpy()` is reached through local `bpf()` operations that load/attach HID-BPF `struct_ops` programs and run a HID-BPF syscall program; it is not reachable directly from remote packets or unauthenticated HID traffic alone.\nAC:L - An attacker who can load the needed HID-BPF programs controls the oversized `hid_hw_request` callback return value and can invoke `hid_bpf_hw_request()` directly, with no race or external timing condition.\nPR:L - Loading HID-BPF requires BPF privileges such as CAP_BPF/CAP_PERFMON, but these can be delegated through BPF tokens into non-init user namespaces in plausible containerized deployments. Choosing the higher-severity option, this is treated as low rather than high privileges.\nUI:N - No victim interaction is required after the attacker has local BPF access; the attacker can attach the callback and run the syscall BPF program themselves.\nS:U - The corruption occurs within the kernel security authority and represents a standard local kernel compromise path, not a VM escape or other cross-scope boundary.\nC:H - The unchecked return value causes an out-of-bounds read from the `dma_data` kernel heap buffer into BPF-accessible memory, allowing disclosure of adjacent kernel memory. As memory corruption, it is also potentially usable to build stronger read primitives.\nI:H - The same unchecked return value is used as the length for `memcpy()` into the caller-provided BPF memory buffer, producing an out-of-bounds kernel write. Such kernel memory corruption is defensibly capable of arbitrary modification or control-flow compromise.\nA:H - A large attacker-controlled copy length can corrupt kernel memory or fault during the copy, causing an oops, panic, or system crash."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T12:22:09.102Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"6.12.78"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"6.18.20"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"6.19.10"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"7.0"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-31401","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T15:08:47.196552Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-120","lang":"en","type":"CWE","description":"CWE-120 Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-19T18:35:46.408Z"}}]}}}