{"id":"CVE-2026-63923","summary":"octeontx2-af: validate body pcifunc in rvu_mbox_handler_rep_event_notify","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nocteontx2-af: validate body pcifunc in rvu_mbox_handler_rep_event_notify\n\nrvu_mbox_handler_rep_event_notify() in drivers/net/ethernet/marvell/\nocteontx2/af/rvu_rep.c queues a sender-controlled REP_EVENT_NOTIFY\nrequest body verbatim, and rvu_rep_up_notify() then forwards\nevent-\u003epcifunc (the nested body field, distinct from the\nAF-normalised header pcifunc) into rvu_get_pfvf(), rvu_get_pf() and\nthe AF-\u003ePF mailbox device index without any bounds check.\n\nA VF attached to a PF that has been put into switchdev\nrepresentor mode reaches this path: the VF mailbox handler\notx2_pfvf_mbox_handler() forwards every message id including\nMBOX_MSG_REP_EVENT_NOTIFY to AF without an allowlist, and the AF\ndispatcher rewrites only msg-\u003epcifunc, leaving struct\nrep_event::pcifunc attacker-controlled.  The sibling\nrvu_mbox_handler_esw_cfg() refuses requests whose header pcifunc\nis not rvu-\u003erep_pcifunc; this handler has no equivalent gate.\n\nAn out-of-range body pcifunc selects an &rvu-\u003epf[]/&rvu-\u003ehwvf[]\nelement past the allocated array and, for RVU_EVENT_MAC_ADDR_CHANGE,\nturns into a six-byte attacker-chosen OOB ether_addr_copy() target\ninside the queued worker; KASAN reports a slab-out-of-bounds write\nin rvu_rep_wq_handler.\n\nReject malformed requests at the handler entry by gating on\nis_pf_func_valid(), which is already the canonical PF/VF range check\nin this driver; expose it via rvu.h so callers in rvu_rep.c can use\nit instead of open-coding the same range arithmetic.","modified":"2026-09-18T10:11:37.589936872Z","published":"2026-07-19T14:55:24.985Z","related":["ALSA-2026:67470","SUSE-SU-2026:23066-1","SUSE-SU-2026:23068-1","SUSE-SU-2026:23221-1","SUSE-SU-2026:23231-1","SUSE-SU-2026:23237-1","SUSE-SU-2026:4120-1","SUSE-SU-2026:4254-1","openSUSE-SU-2026:21555-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63923.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/2156a29aecfffa2eb7c558255690084efbe9f3b0"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4467fa514482bbce82f73788943c815f3d126ab3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/68be0260e2a02ff9b18a8678d5f8d1715fa20138"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63923.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-63923"},{"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":"b8fea84a0468404fe3b3327ad54d583950be9dec"},{"fixed":"4467fa514482bbce82f73788943c815f3d126ab3"},{"fixed":"68be0260e2a02ff9b18a8678d5f8d1715fa20138"},{"fixed":"2156a29aecfffa2eb7c558255690084efbe9f3b0"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63923.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.42"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.0.12"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63923.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H"}]}