{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-64564", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-19T15:36:31.797Z", "datePublished": "2026-08-04T06:23:23.339Z", "dateUpdated": "2026-08-19T16:28:36.947Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-19T16:28:36.947Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: don't free the ASCONF's own transport in DEL-IP processing\n\nsctp_process_asconf() caches the transport the ASCONF chunk is processed\nagainst in asconf->transport (== chunk->transport, set once in sctp_rcv()).\nFor an ASCONF located through its Address Parameter by\n__sctp_rcv_asconf_lookup(), that cached transport corresponds to the\nAddress Parameter, which need not be the packet's source address.\n\nsctp_process_asconf_param() rejects a DEL-IP for the packet source address\n(ADDIP D8, SCTP_ERROR_DEL_SRC_IP), but nothing protects asconf->transport.\nA single ASCONF can therefore carry, in order:\n\n [Address Parameter L] [DEL-IP L] [DEL-IP 0.0.0.0]\n\nwhere L differs from the source. The DEL-IP for L passes the D8 check and\ncalls sctp_assoc_rm_peer() on the transport that asconf->transport still\npoints at, freeing it (RCU-deferred). The following wildcard DEL-IP then\nreuses the now-dangling asconf->transport in sctp_assoc_set_primary() and\nsctp_assoc_del_nonprimary_peers(): set_primary() dereferences the freed\ntransport (->ipaddr, ->state) and plants the dangling pointer into\nasoc->peer.primary_path / active_path, and del_nonprimary_peers(), keeping\nonly the pointer that is no longer on the list, removes every real\ntransport, leaving the association with a transport_count of 0 and\nprimary_path/active_path pointing at freed memory.\n\nReject a DEL-IP that targets the transport the ASCONF is being processed\nagainst, mirroring the existing source-address guard, so the wildcard\nbranch can never reuse a freed transport." } ], "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 SCTP ASCONF receive processing (sctp_rcv → sctp_sf_do_asconf → sctp_process_asconf → sctp_process_asconf_param); a remote peer triggers it by sending a crafted ASCONF over IP/IPv6 on an established association, matching kernel guidance that net/ stack bugs reachable via received packets are Network.\nAC:L - A single attacker-controlled ASCONF with [Address Parameter L][DEL-IP L][DEL-IP 0.0.0.0] reliably frees asconf->transport then reuses it in the same softirq; the peer fully controls multi-homing, serial, and parameter order, with no race or other condition outside attacker influence.\nPR:N - Any remote SCTP peer that completes a normal association with ADD-IP negotiated can send the ASCONF; SCTP-AUTH keys come from the handshake the peer itself performs (or addip_noauth), and no local credentials or capabilities on the target are required.\nUI:N - Exploitation requires only attacker-sent SCTP packets processed automatically in the receive/state-machine path; no victim user action such as opening a file or mounting a device is needed.\nS:U - Impact is confined to the vulnerable host kernel (sctp_transport UAF / crash or privilege escalation) and does not cross a VM, IOMMU, or other security-authority boundary.\nC:H - This is a heap use-after-free of an sctp_transport planted into primary_path/active_path after RCU-deferred free; freed-object reuse yields arbitrary kernel read primitives, scored High per UAF guidance.\nI:H - The same transport UAF enables heap spraying and write/control-flow hijacking via later dereferences of the dangling primary_path/active_path, so integrity impact is High.\nA:H - set_primary() immediately dereferences the freed transport and leaves the association with transport_count 0 and dangling path pointers, causing a reproducible kernel oops/panic on subsequent use, which is High availability impact." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/sctp/sm_make_chunk.c" ], "versions": [ { "version": "42e30bf3463cd37d73839376662cb79b4d5c416c", "lessThan": "a9ce31be4cb1a5dd82b3e0a1d0c3e7cbdcd31293", "status": "affected", "versionType": "git" }, { "version": "42e30bf3463cd37d73839376662cb79b4d5c416c", "lessThan": "a63afa1f9b12d5293cbe0b77fd45dc0632533a13", "status": "affected", "versionType": "git" }, { "version": "42e30bf3463cd37d73839376662cb79b4d5c416c", "lessThan": "2b324ba3494ae958cba16a453e3e71489b4de7fc", "status": "affected", "versionType": "git" }, { "version": "42e30bf3463cd37d73839376662cb79b4d5c416c", "lessThan": "fedeb4468987bcaff85fe3061de5ae052d414740", "status": "affected", "versionType": "git" }, { "version": "42e30bf3463cd37d73839376662cb79b4d5c416c", "lessThan": "74e8f3e7114f0e26d1b2c4c048044db9fcc27603", "status": "affected", "versionType": "git" }, { "version": "42e30bf3463cd37d73839376662cb79b4d5c416c", "lessThan": "85aca407c560aba81b5ce9d3d6cf94c74077d19b", "status": "affected", "versionType": "git" }, { "version": "42e30bf3463cd37d73839376662cb79b4d5c416c", "lessThan": "d136b29bf91dd8e3161281b87de597b7311d9462", "status": "affected", "versionType": "git" }, { "version": "42e30bf3463cd37d73839376662cb79b4d5c416c", "lessThan": "9b2854f86f0b56e9027d68e7a3fc909d1a9b566f", "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/sm_make_chunk.c" ], "versions": [ { "version": "2.6.25", "status": "affected" }, { "version": "0", "lessThan": "2.6.25", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.265", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.216", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.183", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.148", "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": "2.6.25", "versionEndExcluding": "5.10.265" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "5.15.216" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "6.1.183" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "6.6.148" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "6.12.101" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "6.18.42" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "7.1.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/a9ce31be4cb1a5dd82b3e0a1d0c3e7cbdcd31293" }, { "url": "https://git.kernel.org/stable/c/a63afa1f9b12d5293cbe0b77fd45dc0632533a13" }, { "url": "https://git.kernel.org/stable/c/2b324ba3494ae958cba16a453e3e71489b4de7fc" }, { "url": "https://git.kernel.org/stable/c/fedeb4468987bcaff85fe3061de5ae052d414740" }, { "url": "https://git.kernel.org/stable/c/74e8f3e7114f0e26d1b2c4c048044db9fcc27603" }, { "url": "https://git.kernel.org/stable/c/85aca407c560aba81b5ce9d3d6cf94c74077d19b" }, { "url": "https://git.kernel.org/stable/c/d136b29bf91dd8e3161281b87de597b7311d9462" }, { "url": "https://git.kernel.org/stable/c/9b2854f86f0b56e9027d68e7a3fc909d1a9b566f" }, { "url": "https://matrix.tencent.com/en/2026/08/06/sctphantom-CVE-2026-64564" } ], "title": "sctp: don't free the ASCONF's own transport in DEL-IP processing", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "title": "CVE Program Container", "references": [ { "url": "http://www.openwall.com/lists/oss-security/2026/08/06/3" }, { "url": "http://www.openwall.com/lists/oss-security/2026/08/06/4" }, { "url": "http://www.openwall.com/lists/oss-security/2026/08/06/13" }, { "url": "http://www.openwall.com/lists/oss-security/2026/08/07/1" }, { "url": "http://www.openwall.com/lists/oss-security/2026/08/07/2" }, { "url": "http://www.openwall.com/lists/oss-security/2026/08/07/8" } ], "providerMetadata": { "orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2026-08-08T01:31:36.501Z" } } ] } }