159 lines
9.8 KiB
JSON
159 lines
9.8 KiB
JSON
{
|
|
"dataType": "CVE_RECORD",
|
|
"dataVersion": "5.2",
|
|
"cveMetadata": {
|
|
"cveId": "CVE-2025-21954",
|
|
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
|
|
"state": "PUBLISHED",
|
|
"assignerShortName": "Linux",
|
|
"dateReserved": "2024-12-29T08:45:45.790Z",
|
|
"datePublished": "2025-04-01T15:46:55.226Z",
|
|
"dateUpdated": "2026-08-05T11:55:34.681Z"
|
|
},
|
|
"containers": {
|
|
"cna": {
|
|
"providerMetadata": {
|
|
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
|
|
"shortName": "Linux",
|
|
"dateUpdated": "2026-08-05T11:55:34.681Z"
|
|
},
|
|
"descriptions": [
|
|
{
|
|
"lang": "en",
|
|
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetmem: prevent TX of unreadable skbs\n\nCurrently on stable trees we have support for netmem/devmem RX but not\nTX. It is not safe to forward/redirect an RX unreadable netmem packet\ninto the device's TX path, as the device may call dma-mapping APIs on\ndma addrs that should not be passed to it.\n\nFix this by preventing the xmit of unreadable skbs.\n\nTested by configuring tc redirect:\n\nsudo tc qdisc add dev eth1 ingress\nsudo tc filter add dev eth1 ingress protocol ip prio 1 flower ip_proto \\\n\ttcp src_ip 192.168.1.12 action mirred egress redirect dev eth1\n\nBefore, I see unreadable skbs in the driver's TX path passed to dma\nmapping APIs.\n\nAfter, I don't see unreadable skbs in the driver's TX path passed to dma\nmapping APIs."
|
|
}
|
|
],
|
|
"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 unreadable skb is created by the RX path from a packet sent by a remote peer into a dmabuf-bound RX queue, and the bug fires when that received packet is forwarded/bridged/redirected to egress (`ip_forward`/`br_forward`/`act_mirred` → `dev_queue_xmit` → `validate_xmit_skb`). The attacker's only action is transmitting network traffic to the host.\nAC:L - On a host in the affected configuration the trigger is fully deterministic — every forwarded devmem skb reaches `skb_frag_dma_map()` with a NULL page; there is no race window, timing dependency, or memory-layout requirement the attacker must win. `CONFIG_NET_DEVMEM` is `def_bool y`, and per CVSS the vulnerable runtime configuration is assumed rather than charged to complexity.\nPR:N - The remote sender needs no account, credential, or privilege on the target; ordinary unauthenticated packets landing on the devmem-bound queue and being forwarded are sufficient. The CAP_NET_ADMIN-gated `NETDEV_CMD_BIND_RX` is pre-existing admin setup, not something the attacker must perform.\nUI:N - No victim action is required — packet reception and kernel forwarding happen autonomously in softirq context. The devmem binding and forwarding/redirect rules are pre-existing system state, not an interaction solicited from a user.\nS:U - The bogus DMA mapping is programmed by the kernel itself and all consequences (crash, DMA fault, unintended memory access) land within the same host kernel's security authority. No guest/host, IOMMU-enforcement, or sandbox boundary is escaped by the vulnerability itself.\nC:H - The NIC is handed a DMA address derived from a NULL `struct page` that bears no relation to the intended buffer, so on the TX (device-read) path host memory outside any granted buffer can be fetched by the device and transmitted on the wire to the remote peer; the swiotlb path additionally `memcpy`s from `phys_to_virt()` of that garbage address into a bounce buffer that is then sent out.\nI:H - This is a DMA memory-safety violation: the kernel installs a mapping (and on IOMMU systems an active IOVA translation) for a physical range it never owned, and the subsequent `dma_sync`/`dma_unmap` and cache-maintenance operations act on that arbitrary physical range, so memory outside the intended buffer can be modified. Such device-DMA corruption is leveragable well beyond a simple crash.\nA:H - Outcomes include a kernel NULL dereference (`is_pci_p2pdma_page(NULL)`/`swiotlb_bounce()` on confidential-VM and bounce-buffer configurations), DMAR/AER fault storms and TX-ring wedging when the device aborts on the invalid address, and device reset or panic on platforms that escalate the PCIe error — all repeatable at will by continuing to send traffic."
|
|
}
|
|
]
|
|
}
|
|
],
|
|
"affected": [
|
|
{
|
|
"product": "Linux",
|
|
"vendor": "Linux",
|
|
"defaultStatus": "unaffected",
|
|
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
|
|
"programFiles": [
|
|
"net/core/dev.c"
|
|
],
|
|
"versions": [
|
|
{
|
|
"version": "65249feb6b3df9e17bab5911ee56fa7b0971e231",
|
|
"lessThan": "454825019d2f0c59e5174ece9e713f45ad80beff",
|
|
"status": "affected",
|
|
"versionType": "git"
|
|
},
|
|
{
|
|
"version": "65249feb6b3df9e17bab5911ee56fa7b0971e231",
|
|
"lessThan": "1c17c8ced25c5fbe424c7ad7ea11d33014a986b1",
|
|
"status": "affected",
|
|
"versionType": "git"
|
|
},
|
|
{
|
|
"version": "65249feb6b3df9e17bab5911ee56fa7b0971e231",
|
|
"lessThan": "f3600c867c99a2cc8038680ecf211089c50e7971",
|
|
"status": "affected",
|
|
"versionType": "git"
|
|
}
|
|
]
|
|
},
|
|
{
|
|
"product": "Linux",
|
|
"vendor": "Linux",
|
|
"defaultStatus": "affected",
|
|
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
|
|
"programFiles": [
|
|
"net/core/dev.c"
|
|
],
|
|
"versions": [
|
|
{
|
|
"version": "6.12",
|
|
"status": "affected"
|
|
},
|
|
{
|
|
"version": "0",
|
|
"lessThan": "6.12",
|
|
"status": "unaffected",
|
|
"versionType": "semver"
|
|
},
|
|
{
|
|
"version": "6.12.20",
|
|
"lessThanOrEqual": "6.12.*",
|
|
"status": "unaffected",
|
|
"versionType": "semver"
|
|
},
|
|
{
|
|
"version": "6.13.8",
|
|
"lessThanOrEqual": "6.13.*",
|
|
"status": "unaffected",
|
|
"versionType": "semver"
|
|
},
|
|
{
|
|
"version": "6.14",
|
|
"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",
|
|
"versionEndExcluding": "6.12.20"
|
|
},
|
|
{
|
|
"vulnerable": true,
|
|
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
|
|
"versionStartIncluding": "6.12",
|
|
"versionEndExcluding": "6.13.8"
|
|
},
|
|
{
|
|
"vulnerable": true,
|
|
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
|
|
"versionStartIncluding": "6.12",
|
|
"versionEndExcluding": "6.14"
|
|
}
|
|
]
|
|
}
|
|
]
|
|
}
|
|
],
|
|
"references": [
|
|
{
|
|
"url": "https://git.kernel.org/stable/c/454825019d2f0c59e5174ece9e713f45ad80beff"
|
|
},
|
|
{
|
|
"url": "https://git.kernel.org/stable/c/1c17c8ced25c5fbe424c7ad7ea11d33014a986b1"
|
|
},
|
|
{
|
|
"url": "https://git.kernel.org/stable/c/f3600c867c99a2cc8038680ecf211089c50e7971"
|
|
}
|
|
],
|
|
"title": "netmem: prevent TX of unreadable skbs",
|
|
"x_generator": {
|
|
"engine": "bippy-1.2.0"
|
|
}
|
|
}
|
|
}
|
|
} |