{"id":"CVE-2026-99128","title":"sctp: validate chunk length in the inqueue parser","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: validate chunk length in the inqueue parser\n\nSCTP chunks always include a four-byte generic header, but\nsctp_inq_pop() currently accepts shorter declared lengths.…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= bbd0d59809f923ea2b540cbd781b32110e249f6e < cc4a4f1d6b6d725438dc37b97f03d95ed9feb63f","Linux >= bbd0d59809f923ea2b540cbd781b32110e249f6e < b0dbd53b242609c88e81b0a49093bdbef5d5a418","Linux >= bbd0d59809f923ea2b540cbd781b32110e249f6e < d28ea1a62e27210d8ea3cf496dfae85dbdd7b84f","Linux >= bbd0d59809f923ea2b540cbd781b32110e249f6e < 5a7ee52589dae36c93dc64d7a97c5ded84618572","Linux >= bbd0d59809f923ea2b540cbd781b32110e249f6e < e0fb7fe180488a5afa2e91509ea838e8df8cb771","Linux >= bbd0d59809f923ea2b540cbd781b32110e249f6e < 40507f59f230dcf60ae13cb48d34f8c6e9f40659","Linux >= bbd0d59809f923ea2b540cbd781b32110e249f6e < 9ac57e4c62e93c287b36080e5da3645690549990","Linux >= bbd0d59809f923ea2b540cbd781b32110e249f6e < 6cfc1b90cb86f4aabc69fb8e30128e07e2cdfa3a","Linux 2.6.24"],"published":"2026-10-28","updated":"2026-10-30","sourceUpdated":"2026-10-30T12:42:02.124Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-99128","references":[{"url":"https://git.kernel.org/stable/c/cc4a4f1d6b6d725438dc37b97f03d95ed9feb63f"},{"url":"https://git.kernel.org/stable/c/b0dbd53b242609c88e81b0a49093bdbef5d5a418"},{"url":"https://git.kernel.org/stable/c/d28ea1a62e27210d8ea3cf496dfae85dbdd7b84f"},{"url":"https://git.kernel.org/stable/c/5a7ee52589dae36c93dc64d7a97c5ded84618572"},{"url":"https://git.kernel.org/stable/c/e0fb7fe180488a5afa2e91509ea838e8df8cb771"},{"url":"https://git.kernel.org/stable/c/40507f59f230dcf60ae13cb48d34f8c6e9f40659"},{"url":"https://git.kernel.org/stable/c/9ac57e4c62e93c287b36080e5da3645690549990"},{"url":"https://git.kernel.org/stable/c/6cfc1b90cb86f4aabc69fb8e30128e07e2cdfa3a"}],"tags":["cve.org"],"epss":0.00185,"epssPercentile":0.08155,"ingestedAt":"2026-10-28T11:09:40.442Z","slug":"CVE-2026-99128","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nsctp: validate chunk length in the inqueue parser\n\nSCTP chunks always include a four-byte generic header, but\nsctp_inq_pop() currently accepts shorter declared lengths. A zero-length\nchunk leaves chunk_end at the current header.\n\nWhen ASCONF is covered by the association's SCTP-AUTH policy,\nsctp_assoc_bh_rcv() can continue before the state machine performs its\nnormal chunk-length check. sctp_inq_pop() then returns the same malformed\nchunk repeatedly and the receive softirq can lock up.\n\nA remote SCTP peer can trigger this after establishing an association on\na kernel built with CONFIG_IP_SCTP and configured with\nnet.sctp.addip_enable=1 and net.sctp.auth_enable=1. The reproducer did\nnot require application credentials, a shared SCTP AUTH key, or\nnet.sctp.addip_noauth_enable=1.\n\nOn commit f967455fb2a5 (\"seg6: reset IP6CB after IPv6 decapsulation\"),\none zero-length ASCONF caused repeated\nwatchdog soft-lockup reports in a two-vCPU KVM guest. All 3 pre-trigger\nhealth probes succeeded, while 36 of 37 post-trigger probes failed. With\nthis change, all 37 post-trigger probes succeeded and no equivalent\nsoft-lockup signature appeared.\n\nReject chunks shorter than the generic SCTP header at the shared inqueue\nparser boundary. Mark the packet for discard before either caller can\ncontinue processing it, while preserving the four-byte generic minimum.\nDeclared-length 1 through 4 controls and kernel-generated ASCONF traffic\nremained healthy. The patched sctp_hello selftest passed for IPv4 and\nIPv6.\n\nThe complete private reproducer and validation evidence are available\ndirectly to maintainers on request.\n\n## Affected\n\n- `Linux >= bbd0d59809f923ea2b540cbd781b32110e249f6e < cc4a4f1d6b6d725438dc37b97f03d95ed9feb63f`\n- `Linux >= bbd0d59809f923ea2b540cbd781b32110e249f6e < b0dbd53b242609c88e81b0a49093bdbef5d5a418`\n- `Linux >= bbd0d59809f923ea2b540cbd781b32110e249f6e < d28ea1a62e27210d8ea3cf496dfae85dbdd7b84f`\n- `Linux >= bbd0d59809f923ea2b540cbd781b32110e249f6e < 5a7ee52589dae36c93dc64d7a97c5ded84618572`\n- `Linux >= bbd0d59809f923ea2b540cbd781b32110e249f6e < e0fb7fe180488a5afa2e91509ea838e8df8cb771`\n- `Linux >= bbd0d59809f923ea2b540cbd781b32110e249f6e < 40507f59f230dcf60ae13cb48d34f8c6e9f40659`\n- `Linux >= bbd0d59809f923ea2b540cbd781b32110e249f6e < 9ac57e4c62e93c287b36080e5da3645690549990`\n- `Linux >= bbd0d59809f923ea2b540cbd781b32110e249f6e < 6cfc1b90cb86f4aabc69fb8e30128e07e2cdfa3a`\n- `Linux 2.6.24`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}