{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2025-40354",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2025-04-16T07:20:57.187Z",
        "datePublished": "2025-12-16T13:30:27.082Z",
        "dateUpdated": "2026-08-05T12:09:51.348Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-05T12:09:51.348Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/amd/display: increase max link count and fix link->enc NULL pointer access\n\n[why]\n1.) dc->links[MAX_LINKS] array size smaller than actual requested.\nmax_connector + max_dpia + 4 virtual = 14.\nincrease from 12 to 14.\n\n2.) hw_init() access null LINK_ENC for dpia non display_endpoint.\n\n(cherry picked from commit d7f5a61e1b04ed87b008c8d327649d184dc5bb45)"
                }
            ],
            "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 defect is in the amdgpu DC display driver's hardware-init path, reached through local driver probe and suspend/resume (including runtime-PM resume driven by opening /dev/dri/renderD*). There is no network-facing component.\nAC:L - Both the unbounded `dc->links[]` append in create_links() and the NULL `link->link_enc` dereference for DPIA endpoints are deterministic on affected DCN4x configurations — no race to win and no memory layout beyond the attacker's influence.\nPR:L - The vulnerable init_hw path is re-entered on every runtime-PM/system resume via dm_resume() -> dc_set_power_state(D0), which an unprivileged local user holding an ordinary DRM/render node handle can drive repeatedly; no root or CAP_SYS_ADMIN is required.\nUI:N - No victim action is needed — the corrupting create_links() loop runs at driver init and the NULL dereference is hit automatically on each hardware init/resume cycle.\nS:U - The out-of-bounds write and NULL dereference stay within the kernel's own security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - Overflowing dc->links[] overwrites the adjacent `struct link_service *link_srv`, `current_state`, and `res_pool` pointers in struct dc, so subsequent dc->link_srv->...() dispatches read from an attacker-influenceable heap object, yielding pointer confusion and arbitrary kernel-memory read primitives.\nI:H - This is an out-of-bounds write of pointer values past a fixed array directly onto a function-pointer-table pointer (link_srv), giving a realistic indirect-call hijack and arbitrary write path rather than a bounded corruption.\nA:H - The unfixed DPIA path dereferences a NULL link->link_enc in dcn401_init_hw(), producing a kernel oops on every hardware init/resume, and the adjacent-field corruption reliably panics the machine."
                        }
                    ]
                }
            ],
            "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/display/dc/hwss/dcn401/dcn401_hwseq.c",
                        "drivers/gpu/drm/amd/display/dc/inc/hw/hw_shared.h"
                    ],
                    "versions": [
                        {
                            "version": "4562236b3bc0a28aeb6ee93b2d8a849a4c4e1c7c",
                            "lessThan": "f28092be4e12b7df9e4f415d25bf0d767bc2d9ed",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "4562236b3bc0a28aeb6ee93b2d8a849a4c4e1c7c",
                            "lessThan": "a3fc0d36cfb927f8986b83bf5fba47dbedad3c63",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "4562236b3bc0a28aeb6ee93b2d8a849a4c4e1c7c",
                            "lessThan": "bec947cbe9a65783adb475a5fb47980d7b4f4796",
                            "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/display/dc/hwss/dcn401/dcn401_hwseq.c",
                        "drivers/gpu/drm/amd/display/dc/inc/hw/hw_shared.h"
                    ],
                    "versions": [
                        {
                            "version": "4.15",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "4.15",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.56",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.17.6",
                            "lessThanOrEqual": "6.17.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18",
                            "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": "4.15",
                                    "versionEndExcluding": "6.12.56"
                                },
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                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "4.15",
                                    "versionEndExcluding": "6.17.6"
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                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                                    "versionEndExcluding": "6.18"
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            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/f28092be4e12b7df9e4f415d25bf0d767bc2d9ed"
                },
                {
                    "url": "https://git.kernel.org/stable/c/a3fc0d36cfb927f8986b83bf5fba47dbedad3c63"
                },
                {
                    "url": "https://git.kernel.org/stable/c/bec947cbe9a65783adb475a5fb47980d7b4f4796"
                }
            ],
            "title": "drm/amd/display: increase max link count and fix link->enc NULL pointer access",
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