{"id":"CVE-2025-38192","revision":"df9593427f3b4eb68a42abf9c57393d8","records":[{"revision":"df9593427f3b4eb68a42abf9c57393d8","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2025-38192","aliases":[],"title":"net: clear the dst when changing skb protocol","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: clear the dst when changing skb protocol\n\nA not-so-careful NAT46 BPF program can crash the kernel\nif it indiscriminately flips ingress packets from v4 to v6:\n\n  BUG: kernel NULL pointer dereference, address: 0000000000000000\n    ip6_rcv_core (net/ipv6/ip6_input.c:190:20)\n    ipv6_rcv (net/ipv6/ip6_input.c:306:8)\n    process_backlog (net/core/dev.c:6186:4)\n    napi_poll (net/core/dev.c:6906:9)\n    net_rx_action (net/core/dev.c:7028:13)\n    do_softirq (kernel/softirq.c:462:3)\n    netif_rx (net/core/dev.c:5326:3)\n    dev_loopback_xmit (net/core/dev.c:4015:2)\n    ip_mc_finish_output (net/ipv4/ip_output.c:363:8)\n    NF_HOOK (./include/linux/netfilter.h:314:9)\n    ip_mc_output (net/ipv4/ip_output.c:400:5)\n    dst_output (./include/net/dst.h:459:9)\n    ip_local_out (net/ipv4/ip_output.c:130:9)\n    ip_send_skb (net/ipv4/ip_output.c:1496:8)\n    udp_send_skb (net/ipv4/udp.c:1040:8)\n    udp_sendmsg (net/ipv4/udp.c:1328:10)\n\nThe output interface has a 4->6 program attached at ingress.\nWe try to loop the multicast skb back to the sending socket.\nIngress BPF runs as part of netif_rx(), pushes a valid v6 hdr\nand changes skb->protocol to v6. We enter ip6_rcv_core which\ntries to use skb_dst(). But the dst is still an IPv4 one left\nafter IPv4 mcast output.\n\nClear the dst in all BPF helpers which change the protocol.\nTry to preserve metadata dsts, those may carry non-routing\nmetadata.","state":0,"publishedAt":"2025-07-04T13:37:16.642+00:00","modifiedAt":"2026-10-15T21:52:10.856+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"net/core/filter.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"6578171a7ff0c31dc73258f93da7407510abf085\",\n                            \"lessThan\": \"a046f183d21ab5ace5a96ece4cf9873a42f003a7\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"6578171a7ff0c31dc73258f93da7407510abf085\",\n                            \"lessThan\": \"98b1d8dc9a3170b2614f1e8c93854e75cdd83980\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"6578171a7ff0c31dc73258f93da7407510abf085\",\n                            \"lessThan\": \"bfa4d86e130a09f67607482e988313430e38f6c4\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"6578171a7ff0c31dc73258f93da7407510abf085\",\n                            \"lessThan\": \"2a3ad42a57b43145839f2f233fb562247658a6d9\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"6578171a7ff0c31dc73258f93da7407510abf085\",\n                            \"lessThan\": \"e9994e7b9f7bbb882d13c8191731649249150d21\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"6578171a7ff0c31dc73258f93da7407510abf085\",\n                            \"lessThan\": \"ba9db6f907ac02215e30128770f85fbd7db2fcf9\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"net/core/filter.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"4.8\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"4.8\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.209\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.167\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.95\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.35\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.15.4\",\n                            \"lessThanOrEqual\": \"6.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.16\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/a046f183d21ab5ace5a96ece4cf9873a42f003a7","https://git.kernel.org/stable/c/98b1d8dc9a3170b2614f1e8c93854e75cdd83980","https://git.kernel.org/stable/c/bfa4d86e130a09f67607482e988313430e38f6c4","https://git.kernel.org/stable/c/2a3ad42a57b43145839f2f233fb562247658a6d9","https://git.kernel.org/stable/c/e9994e7b9f7bbb882d13c8191731649249150d21","https://git.kernel.org/stable/c/ba9db6f907ac02215e30128770f85fbd7db2fcf9"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2025-38192","license":"CVE Program Terms of Use","key":"cve-program:CVE-2025-38192","identifiers":["CVE-2025-38192"]},"retained":false,"historicalAffected":[]}],"coverage":[]}