235 lines
13 KiB
JSON
235 lines
13 KiB
JSON
{
|
|
"dataType": "CVE_RECORD",
|
|
"dataVersion": "5.2",
|
|
"cveMetadata": {
|
|
"cveId": "CVE-2026-80585",
|
|
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
|
|
"state": "PUBLISHED",
|
|
"assignerShortName": "Linux",
|
|
"dateReserved": "2026-08-26T14:34:25.769Z",
|
|
"datePublished": "2026-08-26T14:37:40.901Z",
|
|
"dateUpdated": "2026-10-16T19:26:28.485Z"
|
|
},
|
|
"containers": {
|
|
"cna": {
|
|
"providerMetadata": {
|
|
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
|
|
"shortName": "Linux",
|
|
"dateUpdated": "2026-08-27T05:02:06.112Z"
|
|
},
|
|
"descriptions": [
|
|
{
|
|
"lang": "en",
|
|
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: fastopen: only mark MPTFO subflows with SYN data\n\nPassive TCP Fast Open accepts a valid-cookie SYN even when it carries\nno data. In that case the child socket's receive queue is intentionally\nleft empty.\n\nmptcp_fastopen_subflow_synack_set_params() set is_mptfo before checking\nfor queued SYN data. That made data-less TFO SYNs hit a WARN and, if\nthe warning was non-fatal, left stale MPTFO state behind. The stale\nflag could later trigger a state-confusion bug in\ncheck_fully_established().\n\nOnly mark the subflow as MPTFO after confirming that an SKB was queued.\nReturn quietly when the receive queue is empty.\n\nNote that mptcp_subflow_context's is_mptfo field is now not just about\nsubflows where the TFO was present, but about MPTFO subflow that\nconsumed SYN data. Only having a valid cookie but not carrying data is\nnot really \"doing TFO\"."
|
|
}
|
|
],
|
|
"metrics": [
|
|
{
|
|
"cvssV3_1": {
|
|
"version": "3.1",
|
|
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H",
|
|
"baseScore": 9.4,
|
|
"baseSeverity": "CRITICAL"
|
|
},
|
|
"scenarios": [
|
|
{
|
|
"lang": "en",
|
|
"value": "AV:N - The bug is reached by sending crafted TCP/MPTCP segments to a listening socket over the network (ip4/ip6 receive -> tcp_conn_request/tcp_rcv_state_process -> subflow_prep_synack or mptcp_incoming_options -> check_fully_established); per kernel CNA guidance, net stack packet-handling paths are Network.\nAC:L - In the intended passive-MPTFO deployment (MPTCP listener with net.ipv4.tcp_fastopen server bit set), the attacker controls obtaining a valid TFO cookie and then sending a data-less SYN followed by an out-of-order MPC_ACK to deterministically hit the stale is_mptfo path in check_fully_established().\nPR:N - Exploitation requires only unauthenticated inbound TCP connections to an MPTCP listener; the attacker obtains the TFO cookie from their own prior connection and needs no local account, capability, or namespace privileges on the target host.\nUI:N - No victim interaction is required beyond the server normally accepting TCP connections; the attacker programmatically sends the SYN and follow-up MPC_ACK packets without anyone opening files, clicking links, or performing other actions.\nS:U - Impact is confined to kernel MPTCP/TCP connection state on the target host and does not cross VM, container, IOMMU, or other security boundaries; it is not a sandbox or guest-to-host escape.\nC:L - Premature fully_established with attacker-chosen MPTCP keys desynchronizes handshake and DSS/map state, enabling misdelivery or premature exposure of connection-level data/metadata to the remote peer before normal MP_CAPABLE validation completes.\nI:H - Stale is_mptfo lets an out-of-order MPC_ACK force __mptcp_subflow_fully_established(), writing attacker-controlled sndr_key/ack_seq into msk and subflow crypto state and corrupting subsequent DSS/ACK handling on the server multipath socket.\nA:H - Data-less passive-TFO SYNs hit WARN_ON_ONCE(!skb) on every trigger, and the resulting inconsistent is_mptfo/fully_established state can cause repeatable kernel WARN/oops (panic_on_warn panic) plus connection reset storms against internet-facing MPTCP servers."
|
|
}
|
|
]
|
|
}
|
|
],
|
|
"affected": [
|
|
{
|
|
"product": "Linux",
|
|
"vendor": "Linux",
|
|
"defaultStatus": "unaffected",
|
|
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
|
|
"programFiles": [
|
|
"net/mptcp/fastopen.c"
|
|
],
|
|
"versions": [
|
|
{
|
|
"version": "36b122baf6a8bd46b4a591f12f4ed17b22257408",
|
|
"lessThan": "f75f174edc865738522e514d042cf5627f084859",
|
|
"status": "affected",
|
|
"versionType": "git"
|
|
},
|
|
{
|
|
"version": "36b122baf6a8bd46b4a591f12f4ed17b22257408",
|
|
"lessThan": "fca7e444c04689fe4cc6b56f2725f804a4bb1ef9",
|
|
"status": "affected",
|
|
"versionType": "git"
|
|
},
|
|
{
|
|
"version": "36b122baf6a8bd46b4a591f12f4ed17b22257408",
|
|
"lessThan": "75e564b2ced1cc3d9a8904c7d2d2bb448fffb8b5",
|
|
"status": "affected",
|
|
"versionType": "git"
|
|
},
|
|
{
|
|
"version": "36b122baf6a8bd46b4a591f12f4ed17b22257408",
|
|
"lessThan": "72b4a0c51a4b550d40301d60a366b429b8c8e78d",
|
|
"status": "affected",
|
|
"versionType": "git"
|
|
},
|
|
{
|
|
"version": "36b122baf6a8bd46b4a591f12f4ed17b22257408",
|
|
"lessThan": "e00b63056fb4f261455b3e5df5268a1f8ce47a87",
|
|
"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/mptcp/fastopen.c"
|
|
],
|
|
"versions": [
|
|
{
|
|
"version": "6.2",
|
|
"status": "affected"
|
|
},
|
|
{
|
|
"version": "0",
|
|
"lessThan": "6.2",
|
|
"status": "unaffected",
|
|
"versionType": "semver"
|
|
},
|
|
{
|
|
"version": "6.6.153",
|
|
"lessThanOrEqual": "6.6.*",
|
|
"status": "unaffected",
|
|
"versionType": "semver"
|
|
},
|
|
{
|
|
"version": "6.12.105",
|
|
"lessThanOrEqual": "6.12.*",
|
|
"status": "unaffected",
|
|
"versionType": "semver"
|
|
},
|
|
{
|
|
"version": "6.18.46",
|
|
"lessThanOrEqual": "6.18.*",
|
|
"status": "unaffected",
|
|
"versionType": "semver"
|
|
},
|
|
{
|
|
"version": "7.1.10",
|
|
"lessThanOrEqual": "7.1.*",
|
|
"status": "unaffected",
|
|
"versionType": "semver"
|
|
},
|
|
{
|
|
"version": "7.2",
|
|
"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": "6.2",
|
|
"versionEndExcluding": "6.6.153"
|
|
},
|
|
{
|
|
"vulnerable": true,
|
|
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
|
|
"versionStartIncluding": "6.2",
|
|
"versionEndExcluding": "6.12.105"
|
|
},
|
|
{
|
|
"vulnerable": true,
|
|
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
|
|
"versionStartIncluding": "6.2",
|
|
"versionEndExcluding": "6.18.46"
|
|
},
|
|
{
|
|
"vulnerable": true,
|
|
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
|
|
"versionStartIncluding": "6.2",
|
|
"versionEndExcluding": "7.1.10"
|
|
},
|
|
{
|
|
"vulnerable": true,
|
|
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
|
|
"versionStartIncluding": "6.2",
|
|
"versionEndExcluding": "7.2"
|
|
}
|
|
]
|
|
}
|
|
]
|
|
}
|
|
],
|
|
"references": [
|
|
{
|
|
"url": "https://git.kernel.org/stable/c/f75f174edc865738522e514d042cf5627f084859"
|
|
},
|
|
{
|
|
"url": "https://git.kernel.org/stable/c/fca7e444c04689fe4cc6b56f2725f804a4bb1ef9"
|
|
},
|
|
{
|
|
"url": "https://git.kernel.org/stable/c/75e564b2ced1cc3d9a8904c7d2d2bb448fffb8b5"
|
|
},
|
|
{
|
|
"url": "https://git.kernel.org/stable/c/72b4a0c51a4b550d40301d60a366b429b8c8e78d"
|
|
},
|
|
{
|
|
"url": "https://git.kernel.org/stable/c/e00b63056fb4f261455b3e5df5268a1f8ce47a87"
|
|
}
|
|
],
|
|
"title": "mptcp: fastopen: only mark MPTFO subflows with SYN data",
|
|
"x_generator": {
|
|
"engine": "bippy-1.2.0"
|
|
}
|
|
},
|
|
"adp": [
|
|
{
|
|
"metrics": [
|
|
{
|
|
"other": {
|
|
"type": "ssvc",
|
|
"content": {
|
|
"id": "CVE-2026-80585",
|
|
"role": "CISA Coordinator",
|
|
"options": [
|
|
{
|
|
"Exploitation": "none"
|
|
},
|
|
{
|
|
"Automatable": "yes"
|
|
},
|
|
{
|
|
"Technical Impact": "partial"
|
|
}
|
|
],
|
|
"version": "2.0.3",
|
|
"timestamp": "2026-10-16T19:17:56.710913Z"
|
|
}
|
|
}
|
|
}
|
|
],
|
|
"title": "CISA ADP Vulnrichment",
|
|
"providerMetadata": {
|
|
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
|
|
"shortName": "CISA-ADP",
|
|
"dateUpdated": "2026-10-16T19:26:28.485Z"
|
|
}
|
|
}
|
|
]
|
|
}
|
|
} |