{"cve":"CVE-2026-99165","nvd":{"published":"2026-10-28T11:17:36.917","modified":"2026-10-28T11:17:36.917","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: revalidate output stream after association connect wait\n\nWhen message interleaving is enabled, the first send waits for association\nestablishment before building its data chunks.  The wait drops the socket\nlock, and handshake processing can reduce the output stream count to the\npeer-advertised inbound stream count.  sctp_stream_init() then frees the\nextension of every removed stream.\n\nThe sender resumes with the stream that it checked before the wait.  If the\npeer removed that stream, sctp_outq_tail() later dereferences its NULL\nextension.  Fatal-oops policies then panic the host.\n\nKASAN: null-ptr-deref in range [0x38-0x3f]\nRIP: sctp_outq_tail+0x49e/0xaa0\nCall Trace:\n sctp_primitive_SEND\n sctp_sendmsg_to_asoc\n sctp_sendmsg\n\nA range check alone is insufficient.  Stream reconfiguration can grow the\noutput count again while the lock is released without recreating extensions\nfreed by the earlier shrink.  The stream can then be in range while its\nextension remains NULL.  The send-buffer wait has the same issue.\n\nFactor the range and extension checks into a helper and repeat both after\neach send-path wait that drops the socket lock.  Once the lock is\nreacquired, the validation remains stable through data creation and\nqueueing.\n\nIf validation fails after the connect wait, the auto-created association is\nalready established.  Return ESRCH so the existing caller path keeps it\nunder state-machine ownership instead of freeing it directly, which would\nleave protocol, counter and socket state inconsistent.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/77a63d1b813b08c4e5a948f5e04fbaca6176aa8f","https://git.kernel.org/stable/c/b7ad72414c673ce1fa1f463e807cd4f34f8be9bf","https://git.kernel.org/stable/c/fd56ac95ec31a05b66e8938debfa847f49c0e993"],"products":[],"source":"nvd","synced_at":"2026-10-28T11:37:51.394563875+00:00"},"epss":null,"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."]}