CVE-2025-21759

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2025-21759", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-12-29T08:45:45.761Z", "datePublished": "2025-02-27T02:18:12.994Z", "dateUpdated": "2026-10-03T10:55:25.159Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-03T10:55:25.159Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: mcast: extend RCU protection in igmp6_send()\n\nigmp6_send() can be called without RTNL or RCU being held.\n\nExtend RCU protection so that we can safely fetch the net pointer\nand avoid a potential UAF.\n\nNote that we no longer can use sock_alloc_send_skb() because\nipv6.igmp_sk uses GFP_KERNEL allocations which can sleep.\n\nInstead use alloc_skb() and charge the net->ipv6.igmp_sk\nsocket under RCU protection."}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH"}, "scenarios": [{"lang": "en", "value": "AV:L - Although igmp6_send() can be scheduled by adjacent MLD Query packets, the freeing side of the race requires network-namespace dismantle or a netdev netns move, which is driven by local syscalls (unshare/setns, RTM_NEWLINK with IFLA_NET_NS_FD, process exit). A local unprivileged user controls both sides of the race entirely, making local access the reliable exploitation vector.\nAC:L - The attacker drives both halves: they schedule igmp6_send() at will (multicast join/leave, link up/down, or timed MLD reports) and trigger the free by destroying their own netns or moving the device out of it, and can retry the race indefinitely while heap-grooming the freed struct net/struct sock.\nPR:L - Only an unprivileged local account is needed \u2014 the CAP_NET_ADMIN checks on the netns-move path are ns_capable() against the target netns user_ns, which is satisfied inside a user namespace created with unshare -Urn, and IPv6 multicast joins require no privilege at all.\nUI:N - The entire sequence \u2014 namespace setup, multicast group joins, and namespace teardown \u2014 is performed by the attacker's own processes with no action from any other user.\nS:U - The corrupted objects (struct net, struct sock) and the resulting code execution are all within the kernel's own security authority; no hypervisor, IOMMU, or other security boundary is crossed.\nC:H - The use-after-free reads sk->sk_sndbuf, sk->sk_allocation, sk->sk_socket, net->mib pointers and net->nf.hooks_ipv6[] from freed-and-reallocated memory, giving an attacker who sprays the freed slab a controllable pointer-dereference primitive that can be turned into arbitrary kernel memory disclosure.\nI:H - skb_set_owner_w() performs refcount_add() into the freed socket and NF_HOOK() calls a function pointer fetched from the freed struct net's netfilter hook array, yielding both a write primitive and control-flow hijack suitable for full privilege escalation.\nA:H - Dereferencing a freed struct net and its igmp_sk reliably produces a kernel oops/panic (slab-use-after-free, invalid pointer dereference in the netfilter or socket accounting path), and the race can be repeated to crash the machine."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/ipv6/mcast.c"], "versions": [{"version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551", "lessThan": "638e8fe3563a82f298fe537a28d5342a97278cf1", "status": "affected", "versionType": "git"}, {"version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551", "lessThan": "6901bbb169e3add6c037218d996790cef6b3d650", "status": "affected", "versionType": "git"}, {"version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551", "lessThan": "7e0a818ecc4d62e7fb668ea02de0bfe8ba0b7dff", "status": "affected", "versionType": "git"}, {"version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551", "lessThan": "81b25a07ebf53f9ef4ca8f3d96a8ddb94561dd5a", "status": "affected", "versionType": "git"}, {"version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551", "lessThan": "0bf8e2f3768629d437a32cb824149e6e98254381", "status": "affected", "versionType": "git"}, {"version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551", "lessThan": "8e92d6a413feaf968a33f0b439ecf27404407458", "status": "affected", "versionType": "git"}, {"version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551", "lessThan": "087c1faa594fa07a66933d750c0b2610aa1a2946", "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/ipv6/mcast.c"], "versions": [{"version": "2.6.26", "status": "affected"}, {"version": "0", "lessThan": "2.6.26", "status": "unaffected", "versionType": "semver"}, {"version": "5.10.271", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.15.222", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.189", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.79", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.16", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.13.4", "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": "2.6.26", "versionEndExcluding": "5.10.271"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.26", "versionEndExcluding": "5.15.222"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.26", "versionEndExcluding": "6.1.189"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.26", "versionEndExcluding": "6.6.79"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.26", "versionEndExcluding": "6.12.16"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.26", "versionEndExcluding": "6.13.4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.26", "versionEndExcluding": "6.14"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/638e8fe3563a82f298fe537a28d5342a97278cf1"}, {"url": "https://git.kernel.org/stable/c/6901bbb169e3add6c037218d996790cef6b3d650"}, {"url": "https://git.kernel.org/stable/c/7e0a818ecc4d62e7fb668ea02de0bfe8ba0b7dff"}, {"url": "https://git.kernel.org/stable/c/81b25a07ebf53f9ef4ca8f3d96a8ddb94561dd5a"}, {"url": "https://git.kernel.org/stable/c/0bf8e2f3768629d437a32cb824149e6e98254381"}, {"url": "https://git.kernel.org/stable/c/8e92d6a413feaf968a33f0b439ecf27404407458"}, {"url": "https://git.kernel.org/stable/c/087c1faa594fa07a66933d750c0b2610aa1a2946"}], "title": "ipv6: mcast: extend RCU protection in igmp6_send()", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"metrics": [{"cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.8, "attackVector": "LOCAL", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH"}}, {"other": {"type": "ssvc", "content": {"id": "CVE-2025-21759", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2025-02-27T17:57:46.460072Z"}}}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-416", "description": "CWE-416 Use After Free"}]}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2025-02-27T18:02:27.454Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.8, "attackVector": "LOCAL", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH"}}, {"other": {"type": "ssvc", "content": {"id": "CVE-2025-21759", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2025-02-27T17:57:46.460072Z"}}}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-416", "description": "CWE-416 Use After Free"}]}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2025-02-27T17:57:47.940Z"}}], "cna": {"title": "ipv6: mcast: extend RCU protection in igmp6_send()", "metrics": [{"cvssV3_1": {"version": "3.1", "baseScore": 7.8, "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}, "scenarios": [{"lang": "en", "value": "AV:L - Although igmp6_send() can be scheduled by adjacent MLD Query packets, the freeing side of the race requires network-namespace dismantle or a netdev netns move, which is driven by local syscalls (unshare/setns, RTM_NEWLINK with IFLA_NET_NS_FD, process exit). A local unprivileged user controls both sides of the race entirely, making local access the reliable exploitation vector.\nAC:L - The attacker drives both halves: they schedule igmp6_send() at will (multicast join/leave, link up/down, or timed MLD reports) and trigger the free by destroying their own netns or moving the device out of it, and can retry the race indefinitely while heap-grooming the freed struct net/struct sock.\nPR:L - Only an unprivileged local account is needed \u2014 the CAP_NET_ADMIN checks on the netns-move path are ns_capable() against the target netns user_ns, which is satisfied inside a user namespace created with unshare -Urn, and IPv6 multicast joins require no privilege at all.\nUI:N - The entire sequence \u2014 namespace setup, multicast group joins, and namespace teardown \u2014 is performed by the attacker's own processes with no action from any other user.\nS:U - The corrupted objects (struct net, struct sock) and the resulting code execution are all within the kernel's own security authority; no hypervisor, IOMMU, or other security boundary is crossed.\nC:H - The use-after-free reads sk->sk_sndbuf, sk->sk_allocation, sk->sk_socket, net->mib pointers and net->nf.hooks_ipv6[] from freed-and-reallocated memory, giving an attacker who sprays the freed slab a controllable pointer-dereference primitive that can be turned into arbitrary kernel memory disclosure.\nI:H - skb_set_owner_w() performs refcount_add() into the freed socket and NF_HOOK() calls a function pointer fetched from the freed struct net's netfilter hook array, yielding both a write primitive and control-flow hijack suitable for full privilege escalation.\nA:H - Dereferencing a freed struct net and its igmp_sk reliably produces a kernel oops/panic (slab-use-after-free, invalid pointer dereference in the netfilter or socket accounting path), and the race can be repeated to crash the machine."}]}], "affected": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551", "lessThan": "638e8fe3563a82f298fe537a28d5342a97278cf1", "versionType": "git"}, {"status": "affected", "version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551", "lessThan": "6901bbb169e3add6c037218d996790cef6b3d650", "versionType": "git"}, {"status": "affected", "version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551", "lessThan": "7e0a818ecc4d62e7fb668ea02de0bfe8ba0b7dff", "versionType": "git"}, {"status": "affected", "version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551", "lessThan": "81b25a07ebf53f9ef4ca8f3d96a8ddb94561dd5a", "versionType": "git"}, {"status": "affected", "version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551", "lessThan": "0bf8e2f3768629d437a32cb824149e6e98254381", "versionType": "git"}, {"status": "affected", "version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551", "lessThan": "8e92d6a413feaf968a33f0b439ecf27404407458", "versionType": "git"}, {"status": "affected", "version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551", "lessThan": "087c1faa594fa07a66933d750c0b2610aa1a2946", "versionType": "git"}], "programFiles": ["net/ipv6/mcast.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "2.6.26"}, {"status": "unaffected", "version": "0", "lessThan": "2.6.26", "versionType": "semver"}, {"status": "unaffected", "version": "5.10.271", "versionType": "semver", "lessThanOrEqual": "5.10.*"}, {"status": "unaffected", "version": "5.15.222", "versionType": "semver", "lessThanOrEqual": "5.15.*"}, {"status": "unaffected", "version": "6.1.189", "versionType": "semver", "lessThanOrEqual": "6.1.*"}, {"status": "unaffected", "version": "6.6.79", "versionType": "semver", "lessThanOrEqual": "6.6.*"}, {"status": "unaffected", "version": "6.12.16", "versionType": "semver", "lessThanOrEqual": "6.12.*"}, {"status": "unaffected", "version": "6.13.4", "versionType": "semver", "lessThanOrEqual": "6.13.*"}, {"status": "unaffected", "version": "6.14", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["net/ipv6/mcast.c"], "defaultStatus": "affected"}], "references": [{"url": "https://git.kernel.org/stable/c/638e8fe3563a82f298fe537a28d5342a97278cf1"}, {"url": "https://git.kernel.org/stable/c/6901bbb169e3add6c037218d996790cef6b3d650"}, {"url": "https://git.kernel.org/stable/c/7e0a818ecc4d62e7fb668ea02de0bfe8ba0b7dff"}, {"url": "https://git.kernel.org/stable/c/81b25a07ebf53f9ef4ca8f3d96a8ddb94561dd5a"}, {"url": "https://git.kernel.org/stable/c/0bf8e2f3768629d437a32cb824149e6e98254381"}, {"url": "https://git.kernel.org/stable/c/8e92d6a413feaf968a33f0b439ecf27404407458"}, {"url": "https://git.kernel.org/stable/c/087c1faa594fa07a66933d750c0b2610aa1a2946"}], "x_generator": {"engine": "bippy-1.2.0"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: mcast: extend RCU protection in igmp6_send()\n\nigmp6_send() can be called without RTNL or RCU being held.\n\nExtend RCU protection so that we can safely fetch the net pointer\nand avoid a potential UAF.\n\nNote that we no longer can use sock_alloc_send_skb() because\nipv6.igmp_sk uses GFP_KERNEL allocations which can sleep.\n\nInstead use alloc_skb() and charge the net->ipv6.igmp_sk\nsocket under RCU protection."}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.10.271", "versionStartIncluding": "2.6.26"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.15.222", "versionStartIncluding": "2.6.26"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.1.189", "versionStartIncluding": "2.6.26"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.6.79", "versionStartIncluding": "2.6.26"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.12.16", "versionStartIncluding": "2.6.26"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.13.4", "versionStartIncluding": "2.6.26"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.14", "versionStartIncluding": "2.6.26"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-03T10:55:25.159Z"}}}, "cveMetadata": {"cveId": "CVE-2025-21759", "state": "PUBLISHED", "dateUpdated": "2026-10-03T10:55:25.159Z", "dateReserved": "2024-12-29T08:45:45.761Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2025-02-27T02:18:12.994Z", "assignerShortName": "Linux"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["net/ipv6/mcast.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "638e8fe3563a82f298fe537a28d5342a97278cf1", "status": "affected", "version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551", "versionType": "git"}, {"lessThan": "6901bbb169e3add6c037218d996790cef6b3d650", "status": "affected", "version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551", "versionType": "git"}, {"lessThan": "7e0a818ecc4d62e7fb668ea02de0bfe8ba0b7dff", "status": "affected", "version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551", "versionType": "git"}, {"lessThan": "81b25a07ebf53f9ef4ca8f3d96a8ddb94561dd5a", "status": "affected", "version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551", "versionType": "git"}, {"lessThan": "0bf8e2f3768629d437a32cb824149e6e98254381", "status": "affected", "version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551", "versionType": "git"}, {"lessThan": "8e92d6a413feaf968a33f0b439ecf27404407458", "status": "affected", "version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551", "versionType": "git"}, {"lessThan": "087c1faa594fa07a66933d750c0b2610aa1a2946", "status": "affected", "version": "b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["net/ipv6/mcast.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "2.6.26"}, {"lessThan": "2.6.26", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "5.10.*", "status": "unaffected", "version": "5.10.271", "versionType": "semver"}, {"lessThanOrEqual": "5.15.*", "status": "unaffected", "version": "5.15.222", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.189", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.79", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.16", "versionType": "semver"}, {"lessThanOrEqual": "6.13.*", "status": "unaffected", "version": "6.13.4", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "6.14", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "80691BA5-295B-4772-9338-1D31A39548D6", "versionEndExcluding": "6.6.79", "versionStartIncluding": "2.6.26", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "13C8DB18-FC60-425F-84E5-3EDDEC61B2FC", "versionEndExcluding": "6.12.16", "versionStartIncluding": "6.7", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "2A2093ED-74A9-43F9-AC72-50030F374EA4", "versionEndExcluding": "6.13.4", "versionStartIncluding": "6.13", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:*", "matchCriteriaId": "186716B6-2B66-4BD0-852E-D48E71C0C85F", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:*", "matchCriteriaId": "0D3E781C-403A-498F-9DA9-ECEE50F41E75", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: mcast: extend RCU protection in igmp6_send()\n\nigmp6_send() can be called without RTNL or RCU being held.\n\nExtend RCU protection so that we can safely fetch the net pointer\nand avoid a potential UAF.\n\nNote that we no longer can use sock_alloc_send_skb() because\nipv6.igmp_sk uses GFP_KERNEL allocations which can sleep.\n\nInstead use alloc_skb() and charge the net->ipv6.igmp_sk\nsocket under RCU protection."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ipv6: mcast: extender la protecci\u00f3n RCU en igmp6_send() igmp6_send() se puede llamar sin que se mantenga RTNL o RCU. Extienda la protecci\u00f3n RCU para que podamos obtener de forma segura el puntero de red y evitar un posible UAF. Tenga en cuenta que ya no podemos usar sock_alloc_send_skb() porque ipv6.igmp_sk usa asignaciones GFP_KERNEL que pueden dormir. En su lugar, use alloc_skb() y cargue el socket net->ipv6.igmp_sk bajo la protecci\u00f3n RCU."}], "id": "CVE-2025-21759", "lastModified": "2026-10-03T11:17:32.400", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}, {"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2025-21759", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2025-02-27T17:57:46.460072Z", "version": "2.0.3"}}]}, "published": "2025-02-27T03:15:16.550", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/087c1faa594fa07a66933d750c0b2610aa1a2946"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/0bf8e2f3768629d437a32cb824149e6e98254381"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/638e8fe3563a82f298fe537a28d5342a97278cf1"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/6901bbb169e3add6c037218d996790cef6b3d650"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/7e0a818ecc4d62e7fb668ea02de0bfe8ba0b7dff"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/81b25a07ebf53f9ef4ca8f3d96a8ddb94561dd5a"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/8e92d6a413feaf968a33f0b439ecf27404407458"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-416"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

{"affected_release": [{"advisory": "RHSA-2025:10371", "cpe": "cpe:/o:redhat:enterprise_linux:10.0", "package": "kernel-0:6.12.0-55.20.1.el10_0", "product_name": "Red Hat Enterprise Linux 10", "release_date": "2025-07-07T00:00:00Z"}, {"advisory": "RHSA-2025:10379", "cpe": "cpe:/a:redhat:enterprise_linux:9", "package": "kernel-0:5.14.0-570.25.1.el9_6", "product_name": "Red Hat Enterprise Linux 9", "release_date": "2025-07-07T00:00:00Z"}, {"advisory": "RHSA-2025:10379", "cpe": "cpe:/o:redhat:enterprise_linux:9", "package": "kernel-0:5.14.0-570.25.1.el9_6", "product_name": "Red Hat Enterprise Linux 9", "release_date": "2025-07-07T00:00:00Z"}], "bugzilla": {"description": "kernel: ipv6: mcast: extend RCU protection in igmp6_send()", "id": "2348596", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2348596"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.0", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "status": "verified"}, "cwe": "CWE-416", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nipv6: mcast: extend RCU protection in igmp6_send()\nigmp6_send() can be called without RTNL or RCU being held.\nExtend RCU protection so that we can safely fetch the net pointer\nand avoid a potential UAF.\nNote that we no longer can use sock_alloc_send_skb() because\nipv6.igmp_sk uses GFP_KERNEL allocations which can sleep.\nInstead use alloc_skb() and charge the net->ipv6.igmp_sk\nsocket under RCU protection."], "mitigation": {"lang": "en:us", "value": "Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability."}, "name": "CVE-2025-21759", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Will not fix", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2025-02-27T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2025-21759\nhttps://nvd.nist.gov/vuln/detail/CVE-2025-21759\nhttps://lore.kernel.org/linux-cve-announce/2025022604-CVE-2025-21759-ad7c@gregkh/T"], "statement": "The bug actual only if IPV6 being used and IGMPv6 (Internet Group Management Protocol for IPv6) being used too. The security impact is limited, because no known way to trigger the bug (see in the patch description: \"Extend RCU protection so that we can safely fetch the net pointer and avoid a potential UAF\").", "threat_severity": "Moderate"}

{}