CVE-2026-63923

Status: UPDATED  |  Advisory ID: CVE-2026-63923

Key Details

Affected Products, Subsystems & Sectors

What to Know

In the Linux kernel, the following vulnerability has been resolved:

octeontx2-af: validate body pcifunc in rvu_mbox_handler_rep_event_notify

rvu_mbox_handler_rep_event_notify() in drivers/net/ethernet/marvell/

octeontx2/af/rvu_rep.c queues a sender-controlled REP_EVENT_NOTIFY

request body verbatim, and rvu_rep_up_notify() then forwards

event->pcifunc (the nested body field, distinct from the

AF-normalised header pcifunc) into rvu_get_pfvf(), rvu_get_pf() and

the AF->PF mailbox device index without any bounds check.

A VF attached to a PF that has been put into switchdev

representor mode reaches this path: the VF mailbox handler

otx2_pfvf_mbox_handler() forwards every message id including

MBOX_MSG_REP_EVENT_NOTIFY to AF without an allowlist, and the AF

dispatcher rewrites only msg->pcifunc, leaving struct

rep_event::pcifunc attacker-controlled. The sibling

rvu_mbox_handler_esw_cfg() refuses requests whose header pcifunc

is not rvu->rep_pcifunc; this handler has no equivalent gate.

An out-of-range body pcifunc selects an &rvu->pf[]/&rvu->hwvf[]

element past the allocated array and, for RVU_EVENT_MAC_ADDR_CHANGE,

turns into a six-byte attacker-chosen OOB ether_addr_copy() target

inside the queued worker; KASAN reports a slab-out-of-bounds write

in rvu_rep_wq_handler.

Reject malformed requests at the handler entry by gating on

is_pf_func_valid(), which is already the canonical PF/VF range check

in this driver; expose it via rvu.h so callers in rvu_rep.c can use

it instead of open-coding the same range arithmetic. (NVD)

What to Do

Monitor Linux's web page for any future patch releases.

References