{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2025-38718", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T04:51:24.033Z", "datePublished": "2025-09-04T15:33:12.448Z", "dateUpdated": "2026-08-05T12:04:15.979Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:04:15.979Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: linearize cloned gso packets in sctp_rcv\n\nA cloned head skb still shares these frag skbs in fraglist with the\noriginal head skb. It's not safe to access these frag skbs.\n\nsyzbot reported two use-of-uninitialized-memory bugs caused by this:\n\n BUG: KMSAN: uninit-value in sctp_inq_pop+0x15b7/0x1920 net/sctp/inqueue.c:211\n sctp_inq_pop+0x15b7/0x1920 net/sctp/inqueue.c:211\n sctp_assoc_bh_rcv+0x1a7/0xc50 net/sctp/associola.c:998\n sctp_inq_push+0x2ef/0x380 net/sctp/inqueue.c:88\n sctp_backlog_rcv+0x397/0xdb0 net/sctp/input.c:331\n sk_backlog_rcv+0x13b/0x420 include/net/sock.h:1122\n __release_sock+0x1da/0x330 net/core/sock.c:3106\n release_sock+0x6b/0x250 net/core/sock.c:3660\n sctp_wait_for_connect+0x487/0x820 net/sctp/socket.c:9360\n sctp_sendmsg_to_asoc+0x1ec1/0x1f00 net/sctp/socket.c:1885\n sctp_sendmsg+0x32b9/0x4a80 net/sctp/socket.c:2031\n inet_sendmsg+0x25a/0x280 net/ipv4/af_inet.c:851\n sock_sendmsg_nosec net/socket.c:718 [inline]\n\nand\n\n BUG: KMSAN: uninit-value in sctp_assoc_bh_rcv+0x34e/0xbc0 net/sctp/associola.c:987\n sctp_assoc_bh_rcv+0x34e/0xbc0 net/sctp/associola.c:987\n sctp_inq_push+0x2a3/0x350 net/sctp/inqueue.c:88\n sctp_backlog_rcv+0x3c7/0xda0 net/sctp/input.c:331\n sk_backlog_rcv+0x142/0x420 include/net/sock.h:1148\n __release_sock+0x1d3/0x330 net/core/sock.c:3213\n release_sock+0x6b/0x270 net/core/sock.c:3767\n sctp_wait_for_connect+0x458/0x820 net/sctp/socket.c:9367\n sctp_sendmsg_to_asoc+0x223a/0x2260 net/sctp/socket.c:1886\n sctp_sendmsg+0x3910/0x49f0 net/sctp/socket.c:2032\n inet_sendmsg+0x269/0x2a0 net/ipv4/af_inet.c:851\n sock_sendmsg_nosec net/socket.c:712 [inline]\n\nThis patch fixes it by linearizing cloned gso packets in sctp_rcv()." } ], "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 - The vulnerable branch requires `skb_is_gso_sctp()`, and `SKB_GSO_SCTP` is set only by the local transmit path (`sk->sk_gso_type` in net/sctp/socket.c:5042, applied in `sctp_packet_pack()`); net/sctp/offload.c registers no GRO handler and virtio/tun cannot carry an SCTP GSO type, so packets arriving from a real network are never `is_gso` and the attacker must originate the packet locally via `sendmsg()` on an SCTP socket looped back over `lo`/`veth`.\nAC:L - The attacker supplies every precondition: an SCTP socket sending more than PMTU to 127.0.0.1 to force the GSO cover-letter skb, and an AF_PACKET or raw socket to guarantee the clone via `dev_queue_xmit_nit()`, all repeatable in a loop; syzbot reproduced it independently twice.\nPR:L - No `capable()` check exists anywhere on the `sendmsg` → `sctp_packet_pack` → `sctp_rcv` → `sctp_inq_pop` path, the SCTP module autoloads on an unprivileged `socket(AF_INET, SOCK_SEQPACKET, IPPROTO_SCTP)`, and the CAP_NET_RAW needed for the cloning tap is obtainable by any local user with `unshare -Urn`.\nUI:N - The attacker performs the send, the clone setup, and the receive entirely from its own processes; no victim action or cooperation is involved.\nS:U - The out-of-bounds accesses and skb metadata corruption occur in kernel heap memory within the same kernel security authority, with no VM, IOMMU, or sandbox boundary crossed.\nC:H - `sctp_inq_pop()` reads chunk headers past the frag skb's valid data (KMSAN uninit-value at inqueue.c:211), and the resulting attacker-influenced `chunk_end`/`datalen` drives `skb_trim()` in `sctp_ulpevent_make_rcvmsg()` on the clone queued for `recvmsg()`, while the co-owner of the shared frags (AF_PACKET/raw socket) reads them at pointers SCTP already advanced — both paths copy adjacent kernel heap out to userspace.\nI:H - SCTP mutates `data`, `len`, and `cb` of frag skbs concurrently owned by another subsystem, and `skb_pull(chunk->skb, sizeof(*ch))` on an already-consumed frag underflows `skb->len` to ~4 GB unchecked, leaving a corrupted length on a live skb while the full SCTP state machine executes on out-of-bounds bytes.\nA:H - The condition is a KASAN/KMSAN-reportable memory-safety violation whose ~4 GB `skb->len` underflow and out-of-range `skb_trim()` produce oops/panic in downstream copy and accounting paths, and any unprivileged local user can retrigger it in a loop." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/sctp/input.c" ], "versions": [ { "version": "90017accff61ae89283ad9a51f9ac46ca01633fb", "lessThan": "d0194e391bb493aa6cec56d177b14df6b29188d5", "status": "affected", "versionType": "git" }, { "version": "90017accff61ae89283ad9a51f9ac46ca01633fb", "lessThan": "03d0cc6889e02420125510b5444b570f4bbf53d5", "status": "affected", "versionType": "git" }, { "version": "90017accff61ae89283ad9a51f9ac46ca01633fb", "lessThan": "cd0e92bb2b7542fb96397ffac639b4f5b099d0cb", "status": "affected", "versionType": "git" }, { "version": "90017accff61ae89283ad9a51f9ac46ca01633fb", "lessThan": "4506bcaabe004d07be8ff09116a3024fbd6aa965", "status": "affected", "versionType": "git" }, { "version": "90017accff61ae89283ad9a51f9ac46ca01633fb", "lessThan": "ea094f38d387d1b0ded5dee4a3e5720aa4ce0139", "status": "affected", "versionType": "git" }, { "version": "90017accff61ae89283ad9a51f9ac46ca01633fb", "lessThan": "7d757f17bc2ef2727994ffa6d5d6e4bc4789a770", "status": "affected", "versionType": "git" }, { "version": "90017accff61ae89283ad9a51f9ac46ca01633fb", "lessThan": "fc66772607101bd2030a4332b3bd0ea3b3605250", "status": "affected", "versionType": "git" }, { "version": "90017accff61ae89283ad9a51f9ac46ca01633fb", "lessThan": "1bd5214ea681584c5886fea3ba03e49f93a43c0e", "status": "affected", "versionType": "git" }, { "version": "90017accff61ae89283ad9a51f9ac46ca01633fb", "lessThan": "fd60d8a086191fe33c2d719732d2482052fa6805", "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/input.c" ], "versions": [ { "version": "4.8", "status": "affected" }, { "version": "0", "lessThan": "4.8", "status": "unaffected", "versionType": "semver" }, { "version": "5.4.297", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.241", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.190", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.162", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.103", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.43", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.15.11", "lessThanOrEqual": "6.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.16.2", "lessThanOrEqual": "6.16.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.17", "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": "4.8", "versionEndExcluding": "5.4.297" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "5.10.241" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "5.15.190" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "6.1.162" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "6.6.103" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "6.12.43" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "6.15.11" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "6.16.2" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "6.17" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/d0194e391bb493aa6cec56d177b14df6b29188d5" }, { "url": "https://git.kernel.org/stable/c/03d0cc6889e02420125510b5444b570f4bbf53d5" }, { "url": "https://git.kernel.org/stable/c/cd0e92bb2b7542fb96397ffac639b4f5b099d0cb" }, { "url": "https://git.kernel.org/stable/c/4506bcaabe004d07be8ff09116a3024fbd6aa965" }, { "url": "https://git.kernel.org/stable/c/ea094f38d387d1b0ded5dee4a3e5720aa4ce0139" }, { "url": "https://git.kernel.org/stable/c/7d757f17bc2ef2727994ffa6d5d6e4bc4789a770" }, { "url": "https://git.kernel.org/stable/c/fc66772607101bd2030a4332b3bd0ea3b3605250" }, { "url": "https://git.kernel.org/stable/c/1bd5214ea681584c5886fea3ba03e49f93a43c0e" }, { "url": "https://git.kernel.org/stable/c/fd60d8a086191fe33c2d719732d2482052fa6805" } ], "title": "sctp: linearize cloned gso packets in sctp_rcv", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "title": "CVE Program Container", "references": [ { "url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html" } ], "providerMetadata": { "orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2025-11-03T17:41:48.713Z" } }, { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2025-38718", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "total" } ], "version": "2.0.3", "timestamp": "2026-06-10T20:40:36.204042Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-06-11T18:44:03.458Z" } } ] } }