{"id":"CVE-2026-68300","aliases":[],"url":"https://o3.security/vulnerability/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->auth_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.","published":"2026-08-10T12:02:34.168Z","modified":"2026-08-14T04:03:56.719007428Z","cvss":{"score":9.8,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"Linux","name":"Kernel","fixedVersion":"6.6.148"}],"fix":null,"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/83f5031f2a6a49d696eb4cc0898345d12f9c6451"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8e04823c120b376ef7dab14b60ebf6823aa16c14"},{"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"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-14T04:03:56.719007428Z"}}