{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-45878", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-05-13T15:03:33.081Z", "datePublished": "2026-05-27T12:16:49.108Z", "dateUpdated": "2026-08-05T12:28:38.911Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:28:38.911Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/amdkfd: Fix watch_id bounds checking in debug address watch v2\n\nThe address watch clear code receives watch_id as an unsigned value\n(u32), but some helper functions were using a signed int and checked\nbits by shifting with watch_id.\n\nIf a very large watch_id is passed from userspace, it can be converted\nto a negative value. This can cause invalid shifts and may access\nmemory outside the watch_points array.\n\ndrm/amdkfd: Fix watch_id bounds checking in debug address watch v2\n\nFix this by checking that watch_id is within MAX_WATCH_ADDRESSES before\nusing it. Also use BIT(watch_id) to test and clear bits safely.\n\nThis keeps the behavior unchanged for valid watch IDs and avoids\nundefined behavior for invalid ones.\n\nFixes the below:\ndrivers/gpu/drm/amd/amdgpu/../amdkfd/kfd_debug.c:448\nkfd_dbg_trap_clear_dev_address_watch() error: buffer overflow\n'pdd->watch_points' 4 <= u32max user_rl='0-3,2147483648-u32max' uncapped\n\ndrivers/gpu/drm/amd/amdgpu/../amdkfd/kfd_debug.c\n 433 int kfd_dbg_trap_clear_dev_address_watch(struct kfd_process_device *pdd,\n 434 uint32_t watch_id)\n 435 {\n 436 int r;\n 437\n 438 if (!kfd_dbg_owns_dev_watch_id(pdd, watch_id))\n\nkfd_dbg_owns_dev_watch_id() doesn't check for negative values so if\nwatch_id is larger than INT_MAX it leads to a buffer overflow.\n(Negative shifts are undefined).\n\n 439 return -EINVAL;\n 440\n 441 if (!pdd->dev->kfd->shared_resources.enable_mes) {\n 442 r = debug_lock_and_unmap(pdd->dev->dqm);\n 443 if (r)\n 444 return r;\n 445 }\n 446\n 447 amdgpu_gfx_off_ctrl(pdd->dev->adev, false);\n--> 448 pdd->watch_points[watch_id] = pdd->dev->kfd2kgd->clear_address_watch(\n 449 pdd->dev->adev,\n 450 watch_id);\n\nv2: (as per, Jonathan Kim)\n - Add early watch_id >= MAX_WATCH_ADDRESSES validation in the set path to\n match the clear path.\n - Drop the redundant bounds check in kfd_dbg_owns_dev_watch_id()." } ], "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 vulnerability is reached only through an ioctl (AMDKFD_IOC_DBG_TRAP) on the local /dev/kfd device node; there is no network or remote path.\nAC:L - The attacker fully controls both the allocation of a watch point and the crafted watch_id; the negative-shift behavior is deterministic on x86, so the out-of-bounds write is triggered reliably and repeatably.\nPR:L - The ioctl has flags=0 with no capability check, and self-debugging (target==p) is permitted, so any unprivileged local user with access to the GPU device node (/dev/kfd) can reach the bug; no root/CAP_SYS_ADMIN is required.\nUI:N - The attacking process performs the enable/allocate/clear sequence entirely on its own; no action by another user is needed.\nS:U - The out-of-bounds write corrupts kernel memory within the same kernel security authority; it does not cross into a separate authority such as a hypervisor or IOMMU boundary.\nC:H - The bug is a kernel out-of-bounds write (memory corruption) that can be groomed to overwrite adjacent kernel structures (e.g., size/pointer fields), which can be leveraged to enable information disclosure.\nI:H - Attacker-influenced out-of-bounds write of a 32-bit value into kernel memory at a controllable offset is a direct kernel memory-corruption/write primitive.\nA:H - The out-of-bounds write into unmapped or critical kernel memory readily causes a kernel oops/panic, producing a denial of service." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/gpu/drm/amd/amdkfd/kfd_debug.c" ], "versions": [ { "version": "e0f85f4690d089cc1a60337decafb1acf7eec45e", "lessThan": "971bf8e61e9b4abaacf9b35eaf76ec222758f9d6", "status": "affected", "versionType": "git" }, { "version": "e0f85f4690d089cc1a60337decafb1acf7eec45e", "lessThan": "a0d367e13db63a6ed76ee0d0a8c3a58c1fa98488", "status": "affected", "versionType": "git" }, { "version": "e0f85f4690d089cc1a60337decafb1acf7eec45e", "lessThan": "2b36c0c1bcbbe15f6cfa9652084b3124c835a150", "status": "affected", "versionType": "git" }, { "version": "e0f85f4690d089cc1a60337decafb1acf7eec45e", "lessThan": "3c38a0f07aa2bfef2b219b1f045534ad93f85afd", "status": "affected", "versionType": "git" }, { "version": "e0f85f4690d089cc1a60337decafb1acf7eec45e", "lessThan": "5a19302cab5cec7ae7f1a60c619951e6c17d8742", "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/gpu/drm/amd/amdkfd/kfd_debug.c" ], "versions": [ { "version": "6.5", "status": "affected" }, { "version": "0", "lessThan": "6.5", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.128", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.75", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.14", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.19.4", "lessThanOrEqual": "6.19.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0", "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": "6.5", "versionEndExcluding": "6.6.128" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.5", "versionEndExcluding": "6.12.75" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.5", "versionEndExcluding": "6.18.14" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.5", "versionEndExcluding": "6.19.4" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.5", "versionEndExcluding": "7.0" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/971bf8e61e9b4abaacf9b35eaf76ec222758f9d6" }, { "url": "https://git.kernel.org/stable/c/a0d367e13db63a6ed76ee0d0a8c3a58c1fa98488" }, { "url": "https://git.kernel.org/stable/c/2b36c0c1bcbbe15f6cfa9652084b3124c835a150" }, { "url": "https://git.kernel.org/stable/c/3c38a0f07aa2bfef2b219b1f045534ad93f85afd" }, { "url": "https://git.kernel.org/stable/c/5a19302cab5cec7ae7f1a60c619951e6c17d8742" } ], "title": "drm/amdkfd: Fix watch_id bounds checking in debug address watch v2", "x_generator": { "engine": "bippy-1.2.0" } } } }