{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-89564", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.725Z", "datePublished": "2026-09-11T19:44:35.131Z", "dateUpdated": "2026-09-11T19:44:35.131Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-09-11T19:44:35.131Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nip: orphan prefetched skbs before multicast forwarding\n\nIPv4 and IPv6 input preserve an skb->sk association installed by\nbpf_sk_assign() so that local delivery can use the selected socket under\nRCU. Both address families can also prefetch a socket in UDP early demux.\nIn both paths (BPF and UDP early demux) a reference is not guaranteed to\nbe held on the socket.\n\nWhen a multicast packet is not locally deliverable, IPv6 hands the\noriginal skb to ip6_mr_input(). IPv4's ip_mr_input() similarly keeps the\noriginal skb when local delivery is not needed. Either path can put the\nskb on an unresolved multicast route queue or forward it after the\nreceive-side RCU section ends.\n\nAfter the prefetched socket is destroyed, a later skb free invokes\nsock_pfree() and dereferences the stale skb->sk. Orphan the skb before\neach non-local multicast forwarding path. Local delivery retains the\noriginal skb; the existing skb_clone() calls provide multicast forwarding\nwith a socket-free clone."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/ipv4/ipmr.c", "net/ipv6/ip6_input.c"], "versions": [{"version": "cf7fbe660f2dbd738ab58aea8e9b0ca6ad232449", "lessThan": "a8af6fbac895f057c4b8ff8a2e3fb4c5827fe4ce", "status": "affected", "versionType": "git"}, {"version": "cf7fbe660f2dbd738ab58aea8e9b0ca6ad232449", "lessThan": "f1281d4b99089fbaf0d3579bba62a814ebb4de4d", "status": "affected", "versionType": "git"}, {"version": "cf7fbe660f2dbd738ab58aea8e9b0ca6ad232449", "lessThan": "e36ce6e78fe3fc3c071a26750783b7ba081ce10d", "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/ipv4/ipmr.c", "net/ipv6/ip6_input.c"], "versions": [{"version": "5.7", "status": "affected"}, {"version": "0", "lessThan": "5.7", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.50", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.4", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.3-rc1", "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": "5.7", "versionEndExcluding": "6.18.50"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.7", "versionEndExcluding": "7.2.4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.7", "versionEndExcluding": "7.3-rc1"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/a8af6fbac895f057c4b8ff8a2e3fb4c5827fe4ce"}, {"url": "https://git.kernel.org/stable/c/f1281d4b99089fbaf0d3579bba62a814ebb4de4d"}, {"url": "https://git.kernel.org/stable/c/e36ce6e78fe3fc3c071a26750783b7ba081ce10d"}], "title": "ip: orphan prefetched skbs before multicast forwarding", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["net/ipv4/ipmr.c", "net/ipv6/ip6_input.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "a8af6fbac895f057c4b8ff8a2e3fb4c5827fe4ce", "status": "affected", "version": "cf7fbe660f2dbd738ab58aea8e9b0ca6ad232449", "versionType": "git"}, {"lessThan": "f1281d4b99089fbaf0d3579bba62a814ebb4de4d", "status": "affected", "version": "cf7fbe660f2dbd738ab58aea8e9b0ca6ad232449", "versionType": "git"}, {"lessThan": "e36ce6e78fe3fc3c071a26750783b7ba081ce10d", "status": "affected", "version": "cf7fbe660f2dbd738ab58aea8e9b0ca6ad232449", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["net/ipv4/ipmr.c", "net/ipv6/ip6_input.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "5.7"}, {"lessThan": "5.7", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.50", "versionType": "semver"}, {"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.4", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.3-rc1", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nip: orphan prefetched skbs before multicast forwarding\n\nIPv4 and IPv6 input preserve an skb->sk association installed by\nbpf_sk_assign() so that local delivery can use the selected socket under\nRCU. Both address families can also prefetch a socket in UDP early demux.\nIn both paths (BPF and UDP early demux) a reference is not guaranteed to\nbe held on the socket.\n\nWhen a multicast packet is not locally deliverable, IPv6 hands the\noriginal skb to ip6_mr_input(). IPv4's ip_mr_input() similarly keeps the\noriginal skb when local delivery is not needed. Either path can put the\nskb on an unresolved multicast route queue or forward it after the\nreceive-side RCU section ends.\n\nAfter the prefetched socket is destroyed, a later skb free invokes\nsock_pfree() and dereferences the stale skb->sk. Orphan the skb before\neach non-local multicast forwarding path. Local delivery retains the\noriginal skb; the existing skb_clone() calls provide multicast forwarding\nwith a socket-free clone."}], "id": "CVE-2026-89564", "lastModified": "2026-09-11T20:19:40.313", "metrics": {}, "published": "2026-09-11T20:19:40.313", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/a8af6fbac895f057c4b8ff8a2e3fb4c5827fe4ce"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/e36ce6e78fe3fc3c071a26750783b7ba081ce10d"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/f1281d4b99089fbaf0d3579bba62a814ebb4de4d"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: Linux Kernel: Use-after-free in IP multicast forwarding can lead to denial of service", "id": "2532326", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2532326"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.9", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-825", "details": ["A flaw was found in the Linux kernel's IP multicast forwarding. When a prefetched socket is destroyed, a subsequent operation to free a network packet (skb) can attempt to access the already freed socket memory. This use-after-free vulnerability can be triggered by a remote attacker sending specially crafted multicast packets. A successful exploit could lead to a system crash, resulting in a Denial of Service (DoS)."], "name": "CVE-2026-89564", "public_date": "2026-09-11T19:44:35Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-89564\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-89564\nhttps://git.kernel.org/stable/c/a8af6fbac895f057c4b8ff8a2e3fb4c5827fe4ce\nhttps://git.kernel.org/stable/c/e36ce6e78fe3fc3c071a26750783b7ba081ce10d\nhttps://git.kernel.org/stable/c/f1281d4b99089fbaf0d3579bba62a814ebb4de4d"], "threat_severity": "Important"}

{}