PT-2026-61240 · Linux · Linux

CVE-2026-63923

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Published

2026-07-19

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Updated

2026-07-19

CVSS v3.1

8.8

High

VectorAV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
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.

Fix

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Related Identifiers

CVE-2026-63923

Affected Products

Linux