{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-89885", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.773Z", "datePublished": "2026-09-16T10:31:49.746Z", "dateUpdated": "2026-10-19T08:54:18.396Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T08:54:18.396Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmedia: platform: mtk-mdp3: Fix SCP device refcounting\n\nmdp_probe() first tries to get the SCP handle with scp_get(). When that\nfails, it falls back to looking up the SCP platform device with\n__get_pdev_by_id() and then reads its driver data.\n\nThe fallback lookup returns the platform device with a reference, just\nlike scp_get() does. However, the fallback path currently drops that\nreference immediately after platform_get_drvdata(). The driver later\nstill calls scp_put(mdp->scp) unconditionally from the probe error path\nand from mdp_video_device_release(), which drops the SCP device\nreference again.\n\nKeep the fallback reference until the existing scp_put() call, so that\nthe fallback path follows the same ownership rules as the scp_get()\npath." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 8.4, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The extra put_device is in mdp_probe()/mdp_video_device_release of the MediaTek MDP3 platform driver, reached only via local driver-model bind on MT8183/MT8195 (boot, deferred probe, module load, or sysfs rebind). No network, Bluetooth/Wi-Fi, or USB path reaches this SCP refcounting.\nAC:L - On MT8183 the MDP RDMA node has no mediatek,scp phandle, so scp_get() fails and the compatible fallback is the production path. That path drops the of_find_device_by_node() ref then later scp_put() extra-puts; cmdq mailbox EPROBE_DEFER after the fallback makes this deterministic with no race.\nPR:N - mdp_probe() runs in driver-core context with no capable() or credential check. On MediaTek Chromebooks, phones, and embedded boards, MDP3 commonly deferred-probes at boot after the SCP fallback, so the extra put fires without a user account.\nUI:N - Platform probe and deferred-probe retries run unattended at boot or module bind on affected hardware. Opening /dev/video, mounting a filesystem, or plugging a device is not required.\nS:U - The extra put_device() use-after-free is of the host SCP platform_device inside the same kernel security authority. It does not cross a VM, IOMMU/DMA, or sandbox boundary.\nC:H - scp_put() extra-puts the SCP platform_device, which can run device_release and free the still-bound struct device. A use-after-free of that object enables reclaim and kernel-memory disclosure.\nI:H - The same device UAF is heap corruption of struct platform_device/mtk_scp still used by the SCP driver and other scp_get() holders, enabling heap spray, arbitrary write, and control-flow hijack.\nA:H - Freeing the SCP device while it remains registered, or later dereferencing the dangling scp pointer from MDP3/vcodec, causes 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/media/platform/mediatek/mdp3/mtk-mdp3-core.c" ], "versions": [ { "version": "db4d27e6bbbf511f9cdb33f682535a0a3cb7c403", "lessThan": "dce13bd9bade3ecc1acb7579397f24743850997f", "status": "affected", "versionType": "git" }, { "version": "31ba1a4d7a5d9466f6ef4910a372b8200f8aad19", "lessThan": "252850653569fdb1a259937e02325cf32c8f0970", "status": "affected", "versionType": "git" }, { "version": "8f6f3aa21517ef34d50808af0c572e69580dca20", "lessThan": "0259ade4c4ceaf1e184a7c1aea8071ad398f9b6f", "status": "affected", "versionType": "git" }, { "version": "8f6f3aa21517ef34d50808af0c572e69580dca20", "lessThan": "55793e4665b7f15151e6f5ab51ca980e73abed5d", "status": "affected", "versionType": "git" }, { "version": "6.12.64", "lessThan": "6.12.110", "status": "affected", "versionType": "semver" }, { "version": "6.18.4", "lessThan": "6.18.51", "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/media/platform/mediatek/mdp3/mtk-mdp3-core.c" ], "versions": [ { "version": "6.19", "status": "affected" }, { "version": "0", "lessThan": "6.19", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.110", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.51", "lessThanOrEqual": "6.18.*", "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": "6.12.64", "versionEndExcluding": "6.12.110" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.18.4", "versionEndExcluding": "6.18.51" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "7.2.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/dce13bd9bade3ecc1acb7579397f24743850997f" }, { "url": "https://git.kernel.org/stable/c/252850653569fdb1a259937e02325cf32c8f0970" }, { "url": "https://git.kernel.org/stable/c/0259ade4c4ceaf1e184a7c1aea8071ad398f9b6f" }, { "url": "https://git.kernel.org/stable/c/55793e4665b7f15151e6f5ab51ca980e73abed5d" } ], "title": "media: platform: mtk-mdp3: Fix SCP device refcounting", "x_generator": { "engine": "bippy-1.2.0" } } } }