---
id: CVE-2026-99122
title: 'vsock/vmci: validate packet source for connected sockets'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  vsock/vmci: validate packet source for connected sockets

  vmci_transport_recv_stream_cb() looks up sockets first by the full source
  and destination tuple, then by desti…
severity: high
cvss: 7.3
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:H'
cvssSource: cna
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= d021c344051af91f42c5ba9fdedc176740cbd238 <
    c027f8b429dbb2157fc1b503df196e272d947c89
  - >-
    Linux >= d021c344051af91f42c5ba9fdedc176740cbd238 <
    90c423b62ec9be08177f74b07a47937ca8d2035b
  - >-
    Linux >= d021c344051af91f42c5ba9fdedc176740cbd238 <
    ad9a7da3fa39c2d616ec0dd3cf6e30531d032fe7
  - Linux 3.9
published: '2026-10-28'
updated: '2026-10-31'
sourceUpdated: '2026-10-31T12:43:23.512Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-99122'
references:
  - url: 'https://git.kernel.org/stable/c/c027f8b429dbb2157fc1b503df196e272d947c89'
  - url: 'https://git.kernel.org/stable/c/90c423b62ec9be08177f74b07a47937ca8d2035b'
  - url: 'https://git.kernel.org/stable/c/ad9a7da3fa39c2d616ec0dd3cf6e30531d032fe7'
tags:
  - cve.org
epss: 0.0012
epssPercentile: 0.01847
ingestedAt: '2026-10-28T11:09:40.443Z'
---

## Overview

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

vsock/vmci: validate packet source for connected sockets

vmci_transport_recv_stream_cb() looks up sockets first by the full source
and destination tuple, then by destination only in the bound table. The
fallback can select a non-listening socket without checking whether the
packet came from its stored peer.

This was reproduced with two VMCI contexts. A RST from the context not
stored in a TCP_SYN_SENT socket reset that socket after it was selected by
the destination-only lookup.

VMCI can process notification packets in bottom-half context when the
socket is not owned by user context, or defer packets to a workqueue. Use
vsock_check_source() after taking the socket lock in the bottom-half path,
and recheck after lock_sock() in the workqueue path. Listening sockets
continue to accept packets from any source.

Reply with a RST addressed from the received packet before dropping a
source that fails validation. This preserves the existing reset behavior
for bound non-listening and concurrently closed sockets without directing
the reset to a connected socket's stored peer.

## Affected

- `Linux >= d021c344051af91f42c5ba9fdedc176740cbd238 < c027f8b429dbb2157fc1b503df196e272d947c89`
- `Linux >= d021c344051af91f42c5ba9fdedc176740cbd238 < 90c423b62ec9be08177f74b07a47937ca8d2035b`
- `Linux >= d021c344051af91f42c5ba9fdedc176740cbd238 < ad9a7da3fa39c2d616ec0dd3cf6e30531d032fe7`
- `Linux 3.9`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.