{"cve":"CVE-2023-53296","nvd":{"published":"2025-09-16T08:15:38.937","modified":"2026-06-17T06:44:46.340","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: check send stream number after wait_for_sndbuf\n\nThis patch fixes a corner case where the asoc out stream count may change\nafter wait_for_sndbuf.\n\nWhen the main thread in the client starts a connection, if its out stream\ncount is set to N while the in stream count in the server is set to N - 2,\nanother thread in the client keeps sending the msgs with stream number\nN - 1, and waits for sndbuf before processing INIT_ACK.\n\nHowever, after processing INIT_ACK, the out stream count in the client is\nshrunk to N - 2, the same to the in stream count in the server. The crash\noccurs when the thread waiting for sndbuf is awake and sends the msg in a\nnon-existing stream(N - 1), the call trace is as below:\n\n  KASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f]\n  Call Trace:\n   <TASK>\n   sctp_cmd_send_msg net/sctp/sm_sideeffect.c:1114 [inline]\n   sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1777 [inline]\n   sctp_side_effects net/sctp/sm_sideeffect.c:1199 [inline]\n   sctp_do_sm+0x197d/0x5310 net/sctp/sm_sideeffect.c:1170\n   sctp_primitive_SEND+0x9f/0xc0 net/sctp/primitive.c:163\n   sctp_sendmsg_to_asoc+0x10eb/0x1a30 net/sctp/socket.c:1868\n   sctp_sendmsg+0x8d4/0x1d90 net/sctp/socket.c:2026\n   inet_sendmsg+0x9d/0xe0 net/ipv4/af_inet.c:825\n   sock_sendmsg_nosec net/socket.c:722 [inline]\n   sock_sendmsg+0xde/0x190 net/socket.c:745\n\nThe fix is to add an unlikely check for the send stream number after the\nthread wakes up from the wait_for_sndbuf.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-476"],"references":["https://git.kernel.org/stable/c/0443fff49d6352160c200064156c25898bd9f58c","https://git.kernel.org/stable/c/2584024b23552c00d95b50255e47bd18d306d31a","https://git.kernel.org/stable/c/667eb99cf7c15fe5b0ecefe75cf658e20ef20c9f","https://git.kernel.org/stable/c/9346a1a21142357972a6f466ba6275ddc54b04ac","https://git.kernel.org/stable/c/a615e7270318fa0b98bf1ff38daf6cf52d840312"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:08:41.295252406+00:00"},"epss":{"cve":"CVE-2023-53296","score":0.00149,"percentile":0.04041,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}