{"id":"CVE-2026-68300","summary":"sctp: auth: verify auth requirement when auth_chunk is NULL","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: auth: verify auth requirement when auth_chunk is NULL\n\nsctp_auth_chunk_verify() returns true unconditionally when\nchunk-\u003eauth_chunk is NULL, silently skipping authentication.\nThis is incorrect when:\n\n1. skb_clone() failed in the BH receive path, leaving auth_chunk\n   NULL. In sctp_endpoint_bh_rcv() asoc is NULL for new\n   connections, so the early sctp_auth_recv_cid() check cannot\n   catch this.\n\n2. No AUTH chunk precedes COOKIE-ECHO, so skb_clone() is never\n   called and auth_chunk remains NULL.\n\nFix by checking sctp_auth_recv_cid() when auth_chunk is NULL:\nif authentication is required, return false to drop the chunk;\notherwise continue normally.","modified":"2026-08-21T03:30:45.042326565Z","published":"2026-08-10T12:02:34.168Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/68xxx/CVE-2026-68300.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/18957373920caf5cdaf5cf32e5d1d7a99ca7700a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/28c5fdce9dd955d2baf5e28987819b6d7cfaf646"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5a022ac51ad83b4ce6c898f4b9eefc65bd26b247"},{"type":"WEB","url":"https://git.kernel.org/stable/c/6caf0e8590c0bf05a76b0d387726adf3a6f3725c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/83f5031f2a6a49d696eb4cc0898345d12f9c6451"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8e04823c120b376ef7dab14b60ebf6823aa16c14"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a129792b3aef15002746c13522781d92ed3522c3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ec2e157fc9678a9bc411305a25aec3fd337d7efb"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/68xxx/CVE-2026-68300.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-68300"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"bbd0d59809f923ea2b540cbd781b32110e249f6e"},{"fixed":"a129792b3aef15002746c13522781d92ed3522c3"},{"fixed":"5a022ac51ad83b4ce6c898f4b9eefc65bd26b247"},{"fixed":"6caf0e8590c0bf05a76b0d387726adf3a6f3725c"},{"fixed":"ec2e157fc9678a9bc411305a25aec3fd337d7efb"},{"fixed":"28c5fdce9dd955d2baf5e28987819b6d7cfaf646"},{"fixed":"18957373920caf5cdaf5cf32e5d1d7a99ca7700a"},{"fixed":"83f5031f2a6a49d696eb4cc0898345d12f9c6451"},{"fixed":"8e04823c120b376ef7dab14b60ebf6823aa16c14"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-68300.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.6.24"},{"fixed":"5.10.265"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.216"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.183"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.148"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.101"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.42"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.6"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-68300.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}