{
  "threat_severity" : "Important",
  "public_date" : "2026-07-19T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: octeontx2-af: validate body pcifunc in rvu_mbox_handler_rep_event_notify",
    "id" : "2502418",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2502418"
  },
  "cvss3" : {
    "cvss3_base_score" : "7.0",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
    "status" : "draft"
  },
  "cwe" : "CWE-787",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nocteontx2-af: validate body pcifunc in rvu_mbox_handler_rep_event_notify\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->pcifunc (the nested body field, distinct from the\nAF-normalised header pcifunc) into rvu_get_pfvf(), rvu_get_pf() and\nthe AF->PF mailbox device index without any bounds check.\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->pcifunc, leaving struct\nrep_event::pcifunc attacker-controlled.  The sibling\nrvu_mbox_handler_esw_cfg() refuses requests whose header pcifunc\nis not rvu->rep_pcifunc; this handler has no equivalent gate.\nAn out-of-range body pcifunc selects an &rvu->pf[]/&rvu->hwvf[]\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.\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.", "A flaw was found in the Linux kernel's `octeontx2-af` driver. A malicious Virtual Function (VF) attached to a Physical Function (PF) in switchdev representor mode can send a specially crafted `REP_EVENT_NOTIFY` message. This message contains an unvalidated `pcifunc` field, which can lead to an out-of-bounds write in the `rvu_rep_wq_handler`. This vulnerability can result in memory corruption, potentially leading to a denial of service." ],
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "fix_state" : "Affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Not affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Not affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat Hardened Images",
    "fix_state" : "Not affected",
    "package_name" : "erlang27",
    "cpe" : "cpe:/a:redhat:hummingbird:1",
    "impact" : "important"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2026-63923\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-63923\nhttps://lore.kernel.org/linux-cve-announce/2026071948-CVE-2026-63923-8d3f@gregkh/T" ],
  "name" : "CVE-2026-63923",
  "csaw" : false
}