{"cve":"CVE-2026-97985","nvd":{"published":"2026-09-25T11:17:26.560","modified":"2026-10-21T13:21:18.350","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\naf_unix: Update last skb marker in manage_oob().\n\nFahad Alharbi reported that blocking recv(MSG_PEEK) could hog CPU\ndue to OOB skb.\n\nIn the following cases, manage_oob() skips OOB skb(s) and returns\nNULL for the last recv(MSG_PEEK):\n\n  socketpair(AF_UNIX, SOCK_STREAM, 0, sk);\n\n  1) skb -> OOB skb -> NULL\n     send(sk[0], \"ab\", 2, MSG_OOB);\n     recv(sk[1], buf, 0, MSG_PEEK);\n\n  2) skb -> consumed OOB skb -> NULL\n     send(sk[0], \"ab\", 2, MSG_OOB);\n     recv(sk[1], buf, 1, MSG_OOB);\n     recv(sk[1], buf, 0, MSG_PEEK);\n\n  3) consumed OOB skb -> OOB skb -> NULL\n     send(sk[0], \"a\", 1, MSG_OOB);\n     recv(sk[1], buf, 0, MSG_OOB);\n     send(sk[0], \"b\", 1, MSG_OOB);\n     recv(sk[1], buf, 1, MSG_PEEK);\n\nThen, @copied is 0 in unix_stream_read_generic() (zero-length buffer,\nor non-OOB skb is not yet consumed), and unix_stream_data_wait() is\ncalled.\n\nHowever, it returns immediately because @last is not updated in\nunix_stream_read_generic(), and the thread busy-waits for a new skb.\n\nLet's update @last in manage_oob().\n\nFor MSG_PEEK, @last is updated with the skipped OOB, and for the\nnon-peek case, @last matches the returned value (when !copied)\nbecause OOB is unlinked.\n\nNote that manage_oob() is inlined and no stack canary is added.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/0630bfc773d85ac44da05b2c5a037dbbd39301ab","https://git.kernel.org/stable/c/94fd4debd2e3a69cf93e766c8b328a810c228119","https://git.kernel.org/stable/c/bd91dc313afe21e9d6b31ca6a47606a33ca5e35c","https://git.kernel.org/stable/c/f1816b3d7ce80dcf086bb68ff5ae6e09520ca1fa","https://git.kernel.org/stable/c/fc62a26493a98a0424d9dae2eb92a1daa1321f65"],"products":[],"source":"nvd","synced_at":"2026-10-22T16:41:11.231219466+00:00"},"epss":{"cve":"CVE-2026-97985","score":0.00168,"percentile":0.06162,"date":"2026-10-25"},"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."]}