{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2025-38421", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T04:51:24.014Z", "datePublished": "2025-07-25T14:16:42.409Z", "dateUpdated": "2026-08-05T12:01:44.968Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:01:44.968Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nplatform/x86/amd: pmf: Use device managed allocations\n\nIf setting up smart PC fails for any reason then this can lead to\na double free when unloading amd-pmf. This is because dev->buf was\nfreed but never set to NULL and is again freed in amd_pmf_remove().\n\nTo avoid subtle allocation bugs in failures leading to a double free\nchange all allocations into device managed allocations." } ], "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 amd-pmf platform driver is reachable only from the local machine — via driver unbind/module unload, the suspend/resume PM path, or the debugfs `update_policy` handler. There is no network or adjacent-network exposure.\nAC:L - On an affected system (AMD laptop whose BIOS advertises Smart PC while the PMF TA/policy is unavailable) `amd_pmf_init_smart_pc()` fails deterministically at every boot, leaving `dev->buf`, `dev->policy_buf` and `dev->prev_data` dangling, so the attacker simply triggers unbind or a suspend/resume cycle to hit the double free/UAF with 100% reliability.\nPR:L - The dangling `pdev->buf` is dereferenced from `amd_pmf_resume_handler()`/`amd_pmf_restore_handler()` and from the re-armed `pb_work` handler, and an unprivileged local user in an active session can initiate suspend/resume through logind; heap grooming to control the reused slab object also needs only unprivileged allocations.\nUI:N - The attacker performs the triggering action themselves (driver unbind/module unload or a suspend/resume cycle); no separate victim needs to be induced into any action.\nS:U - The corrupted memory and the resulting privilege escalation are entirely within the kernel's own security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - The stale `dev->buf`/`dev->prev_data` pointers are read after free (`memcpy(&dev->m_table, dev->buf, dev->mtable_size)` in `amd_pmf_get_smu_info()`), leaking reallocated kernel slab contents, and the double free gives the attacker a slab object shared with another subsystem, which is a general kernel-memory read primitive.\nI:H - The double free of `dev->buf` (and of `policy_buf`/`prev_data`) lets the same slab object be handed to two owners, and the UAF write paths (`memset(dev->buf, 0, dev->mtable_size)`, `dev->prev_data->spl = val`, plus SMU DMA into the freed page programmed by `amd_pmf_set_dram_addr()`) provide a controlled write into live kernel objects, which is exploitable for control-flow hijack.\nA:H - A double free triggers immediate slab freelist corruption — a BUG/panic under freelist hardening or CONFIG_SLUB_DEBUG, and unbounded heap corruption leading to a crash otherwise; the UAF accesses from the PM resume path can be repeated to reliably crash the system." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/platform/x86/amd/pmf/core.c", "drivers/platform/x86/amd/pmf/tee-if.c" ], "versions": [ { "version": "5b1122fc4995f308b21d7cfc64ef9880ac834d20", "lessThan": "0d10b532f861253c283863522d59d099fcb0796d", "status": "affected", "versionType": "git" }, { "version": "5b1122fc4995f308b21d7cfc64ef9880ac834d20", "lessThan": "d9db3a941270d92bbd1a6a6b54a10324484f2f2d", "status": "affected", "versionType": "git" }, { "version": "e70b4b8f93d7fcf8ee063a1d1f18782c4da3d335", "status": "affected", "versionType": "git" }, { "version": "3ed60e51ffdbfef14169bd967e21a6ba5e5ff42b", "status": "affected", "versionType": "git" }, { "version": "6.12.23", "lessThan": "6.13", "status": "affected", "versionType": "semver" }, { "version": "6.13.11", "lessThan": "6.14", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/platform/x86/amd/pmf/core.c", "drivers/platform/x86/amd/pmf/tee-if.c" ], "versions": [ { "version": "6.14", "status": "affected" }, { "version": "0", "lessThan": "6.14", "status": "unaffected", "versionType": "semver" }, { "version": "6.15.4", "lessThanOrEqual": "6.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.16", "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": "6.14", "versionEndExcluding": "6.15.4" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.14", "versionEndExcluding": "6.16" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.12.23" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.13.11" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/0d10b532f861253c283863522d59d099fcb0796d" }, { "url": "https://git.kernel.org/stable/c/d9db3a941270d92bbd1a6a6b54a10324484f2f2d" } ], "title": "platform/x86/amd: pmf: Use device managed allocations", "x_generator": { "engine": "bippy-1.2.0" } } } }