{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "b8fea84a0468404fe3b3327ad54d583950be9dec"
            },
            {
              "fixed": "4467fa514482bbce82f73788943c815f3d126ab3"
            },
            {
              "fixed": "68be0260e2a02ff9b18a8678d5f8d1715fa20138"
            },
            {
              "fixed": "2156a29aecfffa2eb7c558255690084efbe9f3b0"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.42"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.0.12"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63923.json"
  },
  "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 \u0026rvu-\u003epf[]/\u0026rvu-\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.",
  "id": "CVE-2026-63923",
  "modified": "2026-08-12T03:51:33.898904853Z",
  "published": "2026-07-19T14:55:24.985Z",
  "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"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "octeontx2-af: validate body pcifunc in rvu_mbox_handler_rep_event_notify"
}