{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2025-38224",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2025-04-16T04:51:23.995Z",
        "datePublished": "2025-07-04T13:37:39.305Z",
        "dateUpdated": "2026-08-05T12:00:27.874Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-05T12:00:27.874Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncan: kvaser_pciefd: refine error prone echo_skb_max handling logic\n\necho_skb_max should define the supported upper limit of echo_skb[]\nallocated inside the netdevice's priv. The corresponding size value\nprovided by this driver to alloc_candev() is KVASER_PCIEFD_CAN_TX_MAX_COUNT\nwhich is 17.\n\nBut later echo_skb_max is rounded up to the nearest power of two (for the\nmax case, that would be 32) and the tx/ack indices calculated further\nduring tx/rx may exceed the upper array boundary. Kasan reported this for\nthe ack case inside kvaser_pciefd_handle_ack_packet(), though the xmit\nfunction has actually caught the same thing earlier.\n\n BUG: KASAN: slab-out-of-bounds in kvaser_pciefd_handle_ack_packet+0x2d7/0x92a drivers/net/can/kvaser_pciefd.c:1528\n Read of size 8 at addr ffff888105e4f078 by task swapper/4/0\n\n CPU: 4 UID: 0 PID: 0 Comm: swapper/4 Not tainted 6.15.0 #12 PREEMPT(voluntary)\n Call Trace:\n  <IRQ>\n dump_stack_lvl lib/dump_stack.c:122\n print_report mm/kasan/report.c:521\n kasan_report mm/kasan/report.c:634\n kvaser_pciefd_handle_ack_packet drivers/net/can/kvaser_pciefd.c:1528\n kvaser_pciefd_read_packet drivers/net/can/kvaser_pciefd.c:1605\n kvaser_pciefd_read_buffer drivers/net/can/kvaser_pciefd.c:1656\n kvaser_pciefd_receive_irq drivers/net/can/kvaser_pciefd.c:1684\n kvaser_pciefd_irq_handler drivers/net/can/kvaser_pciefd.c:1733\n __handle_irq_event_percpu kernel/irq/handle.c:158\n handle_irq_event kernel/irq/handle.c:210\n handle_edge_irq kernel/irq/chip.c:833\n __common_interrupt arch/x86/kernel/irq.c:296\n common_interrupt arch/x86/kernel/irq.c:286\n  </IRQ>\n\nTx max count definitely matters for kvaser_pciefd_tx_avail(), but for seq\nnumbers' generation that's not the case - we're free to calculate them as\nwould be more convenient, not taking tx max count into account. The only\ndownside is that the size of echo_skb[] should correspond to the max seq\nnumber (not tx max count), so in some situations a bit more memory would\nbe consumed than could be.\n\nThus make the size of the underlying echo_skb[] sufficient for the rounded\nmax tx value.\n\nFound by Linux Verification Center (linuxtesting.org) with Syzkaller."
                }
            ],
            "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 out-of-bounds index is derived from the driver's own monotonically increasing `tx_idx` transmit counter, so it is reached by locally transmitting CAN frames via an AF_CAN socket (`socket`/`bind`/`sendmsg`) on the kvaser_pciefd netdev. Data received from the CAN bus never indexes `echo_skb[]`, so no adjacent/network attacker controls the offset.\nAC:L - The overflow is fully deterministic — `seq = tx_idx & 31` against a 17-entry array means the 18th frame sent lands out of bounds, with no race to win and no memory-layout condition needed to trigger it. Real Kvaser PCIe FD cards report a TX FIFO depth that makes `tx_max_count == 17`, which is exactly the case that rounds up to 32.\nPR:L - `can_create()` in net/can/af_can.c and `raw_sendmsg()` in net/can/raw.c contain no capability checks (only net/can/gw.c gates on CAP_NET_ADMIN), so any unprivileged local user can open a CAN_RAW socket and transmit. The interface being up is the normal operational state of a system fitted with a Kvaser CAN card, not an attacker-supplied precondition.\nUI:N - The attacker triggers the overflow entirely on their own by writing frames to a CAN socket; no victim action, mount, or file open is involved.\nS:U - The heap corruption occurs in kernel memory and is exploited within the same kernel security authority, with no crossing of a VM, IOMMU, or sandbox boundary.\nC:H - KASAN confirmed a slab-out-of-bounds *read* of 8 bytes at `can->can.echo_skb[echo_idx]` beyond the end of the `net_device`+priv allocation; that adjacent-heap value is then treated as an `sk_buff *` and passed through `can_skb_ext_find()`/`netif_rx()`, exposing neighbouring kernel heap contents and enabling further disclosure.\nI:H - Indices 17–31 write past the end of the whole `kvzalloc_flex()` netdev allocation — a NULL store from `start_xmit()`, a live `sk_buff` pointer store from `can_put_echo_skb()`, and another NULL store from `__can_get_echo_skb()` — giving a controlled-offset out-of-bounds write into adjacent slab objects that is leverageable for control-flow hijacking.\nA:H - The out-of-bounds access is a KASAN-reported slab overflow reached from hard IRQ context; treating adjacent heap data as an `sk_buff` and passing it to `netif_rx()`/`dev_kfree_skb_any()` reliably produces an oops or panic, and a vmalloc-backed netdev allocation hits a guard page outright."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/net/can/kvaser_pciefd.c"
                    ],
                    "versions": [
                        {
                            "version": "352fbde14177d608a54120b6ff559ce5b3cf6238",
                            "lessThan": "d8a054b6e6824a8b52c3977ebd38c9583a63efac",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "8256e0ca601051933e9395746817f3801fa9a6bf",
                            "lessThan": "a6550c9aa11e2f57f9cdaa6249cdd44d446be874",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "8256e0ca601051933e9395746817f3801fa9a6bf",
                            "lessThan": "54ec8b08216f3be2cc98b33633d3c8ea79749895",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "f14512f3ee09cda986191c8dd7f54972afa2c763",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "6.12.31",
                            "lessThan": "6.12.35",
                            "status": "affected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.14.9",
                            "lessThan": "6.15",
                            "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/net/can/kvaser_pciefd.c"
                    ],
                    "versions": [
                        {
                            "version": "6.15",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.15",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.35",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.15.4",
                            "lessThanOrEqual": "6.15.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.16",
                            "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": "6.12.31",
                                    "versionEndExcluding": "6.12.35"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.15",
                                    "versionEndExcluding": "6.15.4"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.15",
                                    "versionEndExcluding": "6.16"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.14.9"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/d8a054b6e6824a8b52c3977ebd38c9583a63efac"
                },
                {
                    "url": "https://git.kernel.org/stable/c/a6550c9aa11e2f57f9cdaa6249cdd44d446be874"
                },
                {
                    "url": "https://git.kernel.org/stable/c/54ec8b08216f3be2cc98b33633d3c8ea79749895"
                }
            ],
            "title": "can: kvaser_pciefd: refine error prone echo_skb_max handling logic",
            "x_generator": {
                "engine": "bippy-1.2.0"
            }
        }
    }
}