CVE-2026-99122
Received Received - Intake

Buffer Overflow in Linux Kernel vsock/vmci

Vulnerability report for CVE-2026-99122, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.

Publication date: 2026-10-28

Last updated on: 2026-10-28

Assigner: kernel.org

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.

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Meta Information

Published
2026-10-28
Last Modified
2026-10-28
Generated
2026-10-28
EPSS Evaluated
N/A
NVD
EUVD

Affected Vendors & Products

Showing 4 associated CPEs
Vendor Product Version / Range
Linux Linux d021c344051af91f42c5ba9fdedc176740cbd238
Linux Linux d021c344051af91f42c5ba9fdedc176740cbd238
Linux Linux d021c344051af91f42c5ba9fdedc176740cbd238
Linux Linux 3.9

Helpful Resources

Exploitability

CWE
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KEV
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CWE ID Description
CWE-UNKNOWN

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