{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-89882",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-09-11T19:38:34.772Z",
        "datePublished": "2026-09-16T10:31:47.644Z",
        "dateUpdated": "2026-10-19T08:54:15.482Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-10-19T08:54:15.482Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmedia: rkvdec: hevc: guard INTER_REF_PIC_SET_PRED index underflow\n\nst_ref_pic_set_prediction() computes the reference RPS index as\nst_rps_idx - (delta_idx_minus1 + 1) per HEVC spec equation 7-59.\nBoth operands are u8, so when delta_idx_minus1 + 1 exceeds the\ncurrent index the subtraction wraps and the subsequent array access\nat calculated_rps_st_sets[ref_rps_idx] reads far out of bounds.\n\nA userspace V4L2 client that can open the RKVDEC m2m decoder can\nsubmit an EXT_SPS_ST_RPS control with INTER_REF_PIC_SET_PRED set\nand delta_idx_minus1 crafted to trigger the underflow.\n\nReject the entry early when the reference index would underflow."
                }
            ],
            "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 EXT_SPS_ST_RPS control is applied only via VIDIOC_S_EXT_CTRLS or a media request on the local rkvdec V4L2 m2m node (/dev/videoN), then consumed in rkvdec_hevc_run after QBUF/STREAMON. The HEVC RPS parser is not reachable from the network stack.\nAC:L - The attacker sets INTER_REF_PIC_SET_PRED and a delta_idx_minus1 that makes the u8 index wrap (e.g. idx=0 and delta_idx_minus1=0 yields ref_rps_idx=255). v4l2-ctrls never validates delta_idx_minus1 and try_ctrl only checks SPS, so the out-of-bounds access is deterministic with no race.\nPR:L - rkvdec_open and the ioctl path perform no capability check. An unprivileged local account that can open the decoder node is sufficient, typically via the video group or the Android/embedded media codec service that sandboxed apps can reach.\nUI:N - The attacking process itself opens the decoder, attaches a crafted EXT_SPS_ST_RPS control, queues buffers, and starts streaming. No separate victim action is required.\nS:U - The underflow corrupts kernel heap, stack, and the driver's DMA RPS table inside the same kernel security authority. This is local privilege escalation, not a VM escape, IOMMU bypass, or sandbox-boundary crossing.\nC:H - A wrapped u8 ref_rps_idx indexes calculated_rps_st_sets tens of kilobytes past the kzalloc allocation (up to 255 * sizeof(struct calculated_rps_st_set)). Those out-of-bounds bytes become loop bounds and are copied into the hardware RPS table, giving an attacker-steerable kernel memory read.\nI:H - Out-of-bounds num_delta_pocs overflows the 16-byte stack arrays use_delta_flag and used_by_curr_pic_flag, later loops write past st_rps->delta_poc_s0[16] on the heap, and assemble_hw_st_rps bit-writes rps->info with an unbounded index. That is an attacker-influenced kernel write usable for control-flow hijack.\nA:H - The far out-of-bounds pointer, stack smash, and DMA RPS-table overrun each cause a kernel oops, KASAN report, or wedged decoder, and the attacker can repeat the sequence at will."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/media/platform/rockchip/rkvdec/rkvdec-hevc-common.c"
                    ],
                    "versions": [
                        {
                            "version": "c9a59dc2acc72789d5c778af080d1e65af84862c",
                            "lessThan": "74938f83a8abbee8f502dfb5d94213b2497d1edf",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "c9a59dc2acc72789d5c778af080d1e65af84862c",
                            "lessThan": "052c5ed5a1d96a6b24fd50ccda16fc6841ee7ca3",
                            "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/media/platform/rockchip/rkvdec/rkvdec-hevc-common.c"
                    ],
                    "versions": [
                        {
                            "version": "7.0",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "7.0",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.2.5",
                            "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": "7.0",
                                    "versionEndExcluding": "7.2.5"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "7.0",
                                    "versionEndExcluding": "7.3"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/74938f83a8abbee8f502dfb5d94213b2497d1edf"
                },
                {
                    "url": "https://git.kernel.org/stable/c/052c5ed5a1d96a6b24fd50ccda16fc6841ee7ca3"
                }
            ],
            "title": "media: rkvdec: hevc: guard INTER_REF_PIC_SET_PRED index underflow",
            "x_generator": {
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}