{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-68161", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-30T09:28:09.372Z", "datePublished": "2026-08-10T11:59:28.072Z", "dateUpdated": "2026-08-17T04:59:57.755Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T04:59:57.755Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: close UDP tunnel sockets during netns teardown\n\nproc_sctp_do_udp_port() starts per-net SCTP UDP tunneling sockets when\nnet.sctp.udp_port is set, and stops/restarts them when the sysctl value\nchanges. The netns exit path does not stop these sockets, so a namespace\ncan be torn down while its SCTP UDP tunnel sockets are still installed.\n\nClose the UDP tunnel sockets from sctp_ctrlsock_exit() after unregistering\nthe per-net sysctl table. This prevents new sysctl writes from racing in\nwhile the sockets are being released, and closes the sockets before the\ncontrol socket is destroyed." } ], "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 - Stale SCTP UDP tunnel sockets left installed after netns teardown still receive remote SCTP-over-UDP (RFC 6951) on the configured net.sctp.udp_port; packets enter sctp_udp_rcv→sctp_rcv in softirq and touch freed per-net SCTP/UDP state.\nAC:L - An attacker can repeatedly race namespace deletion against SCTP-over-UDP traffic they send or receive, controlling both teardown timing and packet delivery; no attacker-uncontrollable memory layout or rare kernel config is required beyond SCTP being enabled.\nPR:N - On SCTP-over-UDP deployments where net.sctp.udp_port is already configured, any remote SCTP peer needs no credentials on the target; alternatively an unprivileged local user obtains CAP_NET_ADMIN via user namespaces to set udp_port and destroy the namespace.\nUI:N - Exploitation requires only attacker-driven SCTP-over-UDP traffic and namespace lifecycle events (e.g., container restart); no victim must mount a filesystem, open a file, or take any separate interactive action.\nS:U - Impact is host-kernel slab use-after-free and memory corruption within the same OS security authority; it does not cross VM, IOMMU, or sandbox boundaries to affect a separate security domain.\nC:H - Use-after-free of struct net and SCTP UDP tunnel socket state lets an attacker influence freed slab contents and obtain arbitrary kernel memory read primitives through subsequent SCTP/UDP lookups and socket processing.\nI:H - The UAF enables heap grooming and reuse of freed per-net/socket objects in SCTP/UDP handlers, supporting arbitrary kernel writes and control-flow hijack typical of slab use-after-free exploitation.\nA:H - Dereferencing SCTP/UDP tunnel sockets and per-net state after netns free causes slab use-after-free detections, kernel oops, or panic; even unexploited UAF commonly crashes or hangs the host." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/sctp/protocol.c" ], "versions": [ { "version": "046c052b475e7119b6a30e3483e2888fc606a2f8", "lessThan": "c6eb2d615210b80339548ab07c0230edaab9a6c7", "status": "affected", "versionType": "git" }, { "version": "046c052b475e7119b6a30e3483e2888fc606a2f8", "lessThan": "8ff78591d309c50a4fdab683b68dd8d512a270dd", "status": "affected", "versionType": "git" }, { "version": "046c052b475e7119b6a30e3483e2888fc606a2f8", "lessThan": "3bf0e349cbb4f975f35eb22753acc346b89c66a0", "status": "affected", "versionType": "git" }, { "version": "046c052b475e7119b6a30e3483e2888fc606a2f8", "lessThan": "37ff9794be48d0caa37687e04d09675f9c849121", "status": "affected", "versionType": "git" }, { "version": "046c052b475e7119b6a30e3483e2888fc606a2f8", "lessThan": "ffb2bd7ade36ec4da32c46a6eddbf4515316d08c", "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/sctp/protocol.c" ], "versions": [ { "version": "5.11", "status": "affected" }, { "version": "0", "lessThan": "5.11", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.151", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.101", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.42", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.6", "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": "5.11", "versionEndExcluding": "6.6.151" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "6.12.101" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "6.18.42" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "7.1.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/c6eb2d615210b80339548ab07c0230edaab9a6c7" }, { "url": "https://git.kernel.org/stable/c/8ff78591d309c50a4fdab683b68dd8d512a270dd" }, { "url": "https://git.kernel.org/stable/c/3bf0e349cbb4f975f35eb22753acc346b89c66a0" }, { "url": "https://git.kernel.org/stable/c/37ff9794be48d0caa37687e04d09675f9c849121" }, { "url": "https://git.kernel.org/stable/c/ffb2bd7ade36ec4da32c46a6eddbf4515316d08c" } ], "title": "sctp: close UDP tunnel sockets during netns teardown", "x_generator": { "engine": "bippy-1.2.0" } } } }