CVE-2026-64255 - Vulnerability Details - OpenCVE

In the Linux kernel, the following vulnerability has been resolved: wifi: iwlwifi: mld: validate sta_mask before ffs() in BA session handlers Three BA session handlers use ffs(ba_data->sta_mask) - 1 to derive a station ID without checking that sta_mask is non-zero. When sta_mask is zero, ffs() returns 0 and the subtraction wraps to 0xFFFFFFFF, causing an out-of-bounds access on fw_id_to_link_sta[]. Add WARN_ON_ONCE(!ba_data->sta_mask) guards before each ffs() call, consistent with the existing check in iwl_mld_ampdu_rx_start().

No CVSS v4.0

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

Vendors	Products
Linux	Linux Kernel

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References

Link	Providers
https://git.kernel.org/stable/c/1de92789ce31e46fa7e7d8e89c90b19cdb1c103b
https://git.kernel.org/stable/c/f056fc2b927448d37eca6b6cacc3d1b0f67b20d2
https://git.kernel.org/stable/c/fe7f339f63c9dc4ca546ed7ac38ba4bb3a99dcfc

History

Fri, 24 Jul 2026 18:30:00 +0000

Type	Values Removed	Values Added
Description		In the Linux kernel, the following vulnerability has been resolved: wifi: iwlwifi: mld: validate sta_mask before ffs() in BA session handlers Three BA session handlers use ffs(ba_data->sta_mask) - 1 to derive a station ID without checking that sta_mask is non-zero. When sta_mask is zero, ffs() returns 0 and the subtraction wraps to 0xFFFFFFFF, causing an out-of-bounds access on fw_id_to_link_sta[]. Add WARN_ON_ONCE(!ba_data->sta_mask) guards before each ffs() call, consistent with the existing check in iwl_mld_ampdu_rx_start().
Title		wifi: iwlwifi: mld: validate sta_mask before ffs() in BA session handlers
First Time appeared		Linux Linux linux Kernel
CPEs		cpe:2.3:o:linux:linux_kernel::::::::
Vendors & Products		Linux Linux linux Kernel
References		https://git.kernel.org/stable/c/1de92789ce31e46fa7e7d8e89c90b19cdb1c103b https://git.kernel.org/stable/c/f056fc2b927448d37eca6b6cacc3d1b0f67b20d2 https://git.kernel.org/stable/c/fe7f339f63c9dc4ca546ed7ac38ba4bb3a99dcfc

MITRE

Status: PUBLISHED

Assigner: Linux

Published: 2026-07-24T15:31:22.870Z

Updated: 2026-07-24T15:31:22.870Z

Reserved: 2026-07-19T15:36:31.773Z

Link: CVE-2026-64255

Vulnrichment

No data.

NVD

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Redhat

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OpenCVE Enrichment

No data.

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