CVE-2026-23054

Unknown Unknown - Not Provided

Improper RSS Hash Key Validation in Linux netvsc Causes Hang

Publication date: 2026-02-04

Last updated on: 2026-07-14

Assigner: kernel.org

Description

In the Linux kernel, the following vulnerability has been resolved: net: hv_netvsc: reject RSS hash key programming without RX indirection table RSS configuration requires a valid RX indirection table. When the device reports a single receive queue, rndis_filter_device_add() does not allocate an indirection table, accepting RSS hash key updates in this state leads to a hang. Fix this by gating netvsc_set_rxfh() on ndc->rx_table_sz and return -EOPNOTSUPP when the table is absent. This aligns set_rxfh with the device capabilities and prevents incorrect behavior.

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-02-04

Last Modified

2026-07-14

Generated

2026-07-26

AI Q&A

2026-02-04

EPSS Evaluated

2026-07-25

NVD

CVE-2026-23054

Affected Vendors & Products

Vendor	Product	Version / Range
linux	linux_kernel	*

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-UNKNOWN

Attack-Flow Graph

Executive Summary

This vulnerability exists in the Linux kernel's hv_netvsc network driver. It occurs because the driver accepts RSS (Receive Side Scaling) hash key updates even when the device does not have a valid RX indirection table allocated. Specifically, when the device reports only a single receive queue, the function rndis_filter_device_add() does not allocate this table. Accepting RSS hash key updates in this state causes the system to hang.

The fix involves modifying the netvsc_set_rxfh() function to check for the presence of the RX indirection table size (ndc->rx_table_sz) and return an error (-EOPNOTSUPP) if the table is absent. This ensures that RSS hash key programming is only allowed when the device supports it, preventing the hang.

Detection Guidance

I don't know

Impact Analysis

This vulnerability can cause the affected Linux system to hang when RSS hash key updates are applied without a valid RX indirection table. A system hang can lead to denial of service, disrupting network operations and potentially requiring a system reboot to recover.

Compliance Impact

I don't know

Mitigation Strategies

The vulnerability is fixed by ensuring that RSS hash key programming is only accepted when a valid RX indirection table is present. To mitigate this vulnerability immediately, update your Linux kernel to a version that includes the fix which gates netvsc_set_rxfh() on the presence of the RX indirection table and returns -EOPNOTSUPP when the table is absent.

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