{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-89442", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.703Z", "datePublished": "2026-09-11T19:43:10.753Z", "dateUpdated": "2026-10-19T08:46:51.770Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T08:46:51.770Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nplatform/x86: ISST: Validate socket ID in clos_assoc ioctl\n\nisst_if_clos_assoc() validates the user-supplied socket_id with\n'socket_id > topology_max_packages()', but isst_common.sst_inst[] is\nallocated with topology_max_packages() entries, so the valid index range\nis [0, topology_max_packages()). The '>' comparison lets\nsocket_id == topology_max_packages() pass and index one entry past the\narray.\n\nIn addition, isst_common.sst_inst[socket_id] is NULL for an in-range\npackage that has no bound TPMI SST instance, and the pointer is used\nwithout a NULL check. Both the out-of-bounds entry and the NULL pointer\nare then dereferenced by map_partition_power_domain_id() and the\nfollowing power_domain_info access.\n\nReject socket_id >= topology_max_packages() and a NULL sst_inst, matching\nthe checks already performed by get_instance()." } ], "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 bug is reached only through the ISST_IF_CLOS_ASSOC ioctl on /dev/isst_interface; isst_if_clos_assoc() is not invoked from network, Bluetooth, or USB processing.\nAC:L - The attacker sets punit_cpu_map=1 and socket_id equal to topology_max_packages() (one past sst_inst[]) or to an in-range unbound package (NULL sst_inst). Both are deterministic ioctl inputs with no race or victim state.\nPR:L - isst_if_open() has no capability check, and capable(CAP_SYS_ADMIN) runs only on the SET path after sst_inst is already indexed and dereferenced, so an unprivileged local user with the device fd can trigger it via GET.\nUI:N - The attacker issues the ioctl directly against /dev/isst_interface; no victim action such as mounting a filesystem or opening a file is required.\nS:U - The out-of-bounds pointer load and subsequent NULL or wild dereference stay in the kernel ISST driver and do not cross a VM, IOMMU, or sandbox boundary.\nC:H - socket_id == topology_max_packages() reads one pointer past sst_inst[] and treats it as struct tpmi_sst_struct; map_partition_power_domain_id() and readq() follow that object, and GET copy_to_user discloses the result as a kernel-memory read primitive.\nI:H - Treating the adjacent out-of-bounds pointer as sst_inst is type confusion; the confused object supplies sst_base used for writeq() on the SET path and further structure walks, which is an exploitable kernel write primitive.\nA:H - A NULL sst_inst or garbage out-of-bounds pointer is immediately dereferenced in map_partition_power_domain_id() and the following power_domain_info access, causing a kernel oops or panic." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/platform/x86/intel/speed_select_if/isst_tpmi_core.c" ], "versions": [ { "version": "12a7d2cb811dd8a884dea088a2701fcb8d00136e", "lessThan": "c847ea4851ecfa3462cc711ded2c3c3dd8d08ab8", "status": "affected", "versionType": "git" }, { "version": "12a7d2cb811dd8a884dea088a2701fcb8d00136e", "lessThan": "0d90ab5f80e19cddfeb0c9fab47a1f34aa932075", "status": "affected", "versionType": "git" }, { "version": "12a7d2cb811dd8a884dea088a2701fcb8d00136e", "lessThan": "82e707eff9e3b7ef6d96ecc23ea8876d20c7d6ca", "status": "affected", "versionType": "git" }, { "version": "12a7d2cb811dd8a884dea088a2701fcb8d00136e", "lessThan": "207b4dc6eb100141b122b2602504a1429a4b6558", "status": "affected", "versionType": "git" }, { "version": "12a7d2cb811dd8a884dea088a2701fcb8d00136e", "lessThan": "a89f07db0cb95c54dac4a8406c79a04e44a73c3c", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/platform/x86/intel/speed_select_if/isst_tpmi_core.c" ], "versions": [ { "version": "6.4", "status": "affected" }, { "version": "0", "lessThan": "6.4", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.157", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.109", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.50", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.4", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.4", "versionEndExcluding": "6.6.157" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.4", "versionEndExcluding": "6.12.109" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.4", "versionEndExcluding": "6.18.50" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.4", "versionEndExcluding": "7.2.4" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.4", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/c847ea4851ecfa3462cc711ded2c3c3dd8d08ab8" }, { "url": "https://git.kernel.org/stable/c/0d90ab5f80e19cddfeb0c9fab47a1f34aa932075" }, { "url": "https://git.kernel.org/stable/c/82e707eff9e3b7ef6d96ecc23ea8876d20c7d6ca" }, { "url": "https://git.kernel.org/stable/c/207b4dc6eb100141b122b2602504a1429a4b6558" }, { "url": "https://git.kernel.org/stable/c/a89f07db0cb95c54dac4a8406c79a04e44a73c3c" } ], "title": "platform/x86: ISST: Validate socket ID in clos_assoc ioctl", "x_generator": { "engine": "bippy-1.2.0" } } } }