CVE-2026-99122

HIGH
MEDIUM Priority: 0.01 BB Relevance: 40/100
Published: 2026-10-28 Modified: 2026-10-31 First seen: 2026-10-29 Status: active

Attack Surface

Low Complexity No Interaction Scope Change

CVSS Vector Breakdown

AV: Local
AC: Low
PR: Low
UI: None
S: Changed
C: Low
I: None
A: High

Description

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 Software (5)

VendorProductVersion
Linux Linux d021c344051af91f42c5ba9fdedc176740cbd238 < c027f8b429dbb2157fc1b503df196e272d947c89
Linux Linux d021c344051af91f42c5ba9fdedc176740cbd238 < c027f8b429dbb2157fc1b503df196e272d947c89
Linux Linux d021c344051af91f42c5ba9fdedc176740cbd238 < 90c423b62ec9be08177f74b07a47937ca8d2035b
Linux Linux d021c344051af91f42c5ba9fdedc176740cbd238 < ad9a7da3fa39c2d616ec0dd3cf6e30531d032fe7
Linux Linux 3.9

Bug Bounty Relevance

40 / 100
✓ Low complexity
✓ No user interaction

CVSS Score

7.3 / 10.0 v3.1
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:H

EPSS — Exploitation Probability

0.12%
Raw Score 0.001200
Percentile 1.8%
Date 2026-11-01

EPSS Trend

2026-11-01
0.00120
2026-10-31
0.00167
2026-10-30
0.00167
2026-10-29
0.00167

Intelligence Sources

mitre ref →
nvd ref →