CVE-2026-98887: wifi: mac80211_hwsim: reject undersized HWSIM_ATTR_TX_INFO

Severity: unknown
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-10-23 · updated 2026-10-26

Description

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211_hwsim: reject undersized HWSIM_ATTR_TX_INFO hwsim_tx_info_frame_received_nl() casts the HWSIM_ATTR_TX_INFO payload to a struct hwsim_tx_rate * and unconditionally reads IEEE80211_TX_MAX_RATES entries (8 bytes) from it. The policy only bounds the attribute from above (NLA_BINARY .len is a maximum) and the op sets GENL_DONT_VALIDATE_STRICT, so a short or zero-length attribute is accepted and the loop reads past the payload. Require the exact length in the policy, so a malformed attribute is rejected before the handler runs.

Affected products

Linux kernel: before 5.10.271; before 5.15.222; before 6.1.189; before 6.6.158; before 6.12.111; before 6.18.53 — fixed in 5.10.271, 5.15.222, 6.1.189, 6.12.111, 6.18.53, 6.6.158

How to fix

Upgrade to a fixed version: Linux kernel 5.10.271, 5.15.222, 6.1.189, 6.12.111. Check the vendor advisory for mitigations.

References

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