{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-63857",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-07-19T07:54:57.016Z",
        "datePublished": "2026-07-19T14:04:46.339Z",
        "dateUpdated": "2026-08-05T12:36:35.977Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-05T12:36:35.977Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: airoha: Do not read uninitialized fragment address in airoha_dev_xmit()\n\nThe transmit loop in airoha_dev_xmit() reads fragment address and length\nduring its final iteration, when the loop index equals\nskb_shinfo(skb)->nr_frags, at which point the fragment data is\nuninitialized. While these values are never consumed, the read itself is\nunsafe and may trigger a page fault. Fix this by avoiding the fragment\nread on the last iteration.\nAdditionally, move the skb pointer from the first to the last used packet\ndescriptor, so that airoha_qdma_tx_napi_poll() defers freeing the skb\nuntil the final descriptor is processed."
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
                        "baseScore": 9.8,
                        "baseSeverity": "CRITICAL"
                    },
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "AV:N - The bug is in netdev TX (`ndo_start_xmit`) on Airoha EN7581 WAN/LAN interfaces; a remote attacker can trigger transmission by sending packets that cause responses, NAT forwarding, or bridged/routed egress without local access.\nAC:L - Any outbound skb traversing this driver hits the defective loop deterministically; an attacker can reliably provoke multi-fragment transmits (scatter/gather is enabled) to also trigger the premature-skb-free UAF without depending on uncontrollable timing or layout.\nPR:N - Exploitation requires only the ability to send network traffic to or through the device's registered netdevs; no local account, capability, or authentication is needed on internet-facing router/CPE deployments.\nUI:N - No victim interaction is required beyond normal always-on network traffic handled by the kernel stack.\nS:U - Impact is confined to kernel memory and the host running the Airoha driver; it does not cross a VM/hypervisor or IOMMU security boundary.\nC:H - The final loop iteration performs an out-of-bounds read of uninitialized `skb_frag_t` contents that may contain stale kernel heap data, and the companion skb lifetime bug creates a use-after-free that can be leveraged for arbitrary kernel memory disclosure.\nI:H - Premature freeing of the skb while later TX descriptors still DMA mapped fragment memory is a heap use-after-free that can be exploited for arbitrary kernel writes or code execution, not merely a discarded read.\nA:H - Reading garbage fragment metadata can cause a kernel page fault/oops, and the skb use-after-free can crash or panic the system during subsequent DMA completion or skb reuse."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/net/ethernet/airoha/airoha_eth.c"
                    ],
                    "versions": [
                        {
                            "version": "23020f04932701d5c8363e60756f12b43b8ed752",
                            "lessThan": "f670fa4b19ceddc6d215dda4997888ccba9bbc61",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "23020f04932701d5c8363e60756f12b43b8ed752",
                            "lessThan": "d78c8ab7bd84952e053d0c622b7fc1b4ad8a19a3",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "23020f04932701d5c8363e60756f12b43b8ed752",
                            "lessThan": "bde34e84edc8b5571fbde7e941e175a4293ee1eb",
                            "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/net/ethernet/airoha/airoha_eth.c"
                    ],
                    "versions": [
                        {
                            "version": "6.11",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.11",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.33",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.0.10",
                            "lessThanOrEqual": "7.0.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.1",
                            "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": "6.11",
                                    "versionEndExcluding": "6.18.33"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.11",
                                    "versionEndExcluding": "7.0.10"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.11",
                                    "versionEndExcluding": "7.1"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/f670fa4b19ceddc6d215dda4997888ccba9bbc61"
                },
                {
                    "url": "https://git.kernel.org/stable/c/d78c8ab7bd84952e053d0c622b7fc1b4ad8a19a3"
                },
                {
                    "url": "https://git.kernel.org/stable/c/bde34e84edc8b5571fbde7e941e175a4293ee1eb"
                }
            ],
            "title": "net: airoha: Do not read uninitialized fragment address in airoha_dev_xmit()",
            "x_generator": {
                "engine": "bippy-1.2.0"
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}