CVE-2023-52832

What it actually does

The flaw allows ieee80211_get_tx_power() to return INT_MIN (the internal sentinel for unset power level), which when multiplied by 100 in nl80211_send_iface triggers a signed integer overflow detectable by UBSAN in the wireless netlink interface path.

Why it matters to the business

Wireless device registration or interface queries on affected Linux kernels can produce kernel warnings or crashes during module load or configuration, disrupting Wi-Fi functionality and requiring kernel updates across large fleets of servers, embedded devices, and Android-based systems.

How an attack unfolds

An attacker with the ability to trigger wireless interface registration (for example via insmod of a mac80211-based driver or network configuration) causes the kernel to call ieee80211_get_tx_power and return the sentinel value, leading to the UBSAN-detected overflow in nl80211. Threat actors referenced in Android kernel RCE contexts may chain this memory corruption primitive with other bugs to achieve code execution.

How to fix it

Update the Linux kernel to a version containing commit 717de20abdcd1d4993fa450e28b8086a352620ea or later stable releases that prevent returning the unset power sentinel from ieee80211_get_tx_power(). Rebuild and deploy the updated kernel across all affected systems.

How to confirm the fix worked

Confirm the kernel source contains commit 717de20abdcd1d4993fa450e28b8086a352620ea, verify that ieee80211_get_tx_power returns an error instead of INT_MIN when power is unset, and test wireless interface registration without triggering UBSAN warnings.

Typical attack path

1. Load or initialize a mac80211 wireless driver that registers hardware with cfg80211
2. Trigger ieee80211_get_tx_power() returning the internal INT_MIN sentinel
3. Invoke nl80211_send_iface which performs the multiplication by 100
4. Trigger signed integer overflow resulting in UBSAN report or potential memory corruption

How to detect it

Review kernel logs for UBSAN signed-integer-overflow messages referencing nl80211.c:3816 or ieee80211_get_tx_power during module load or wireless interface registration; correlate with process names such as insmod and driver initialization events.

What your security team should do

• Prioritize kernel updates on all systems exposing wireless interfaces or using mac80211 drivers
• Monitor for UBSAN reports or integer overflow warnings during driver initialization
• Apply the fix within standard patch windows given the absence of active KEV or ransomware exploitation