Use After Free Vulnerability in Linux Kernel Affecting WiFi Functionality

CVE-2022-49934

What is CVE-2022-49934?

A use after free vulnerability exists in the Linux kernel's mac80211 subsystem. Specifically, in the ieee80211_scan_rx() function, a reference to scan_req->flags is made after a null check, leading to the risk of accessing freed memory when a WiFi scan completes. The vulnerability arises when __ieee80211_scan_completed() executes and calls cfg80211_scan_done(), ultimately freeing scan_req. To mitigate this issue, precautions must be enforced to avoid accessing scan_req within the RCU read critical section before calling cfg80211_scan_done(), ensuring system stability and integrity.

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