CVE-2021-27803

wpa_supplicant P2P provision discovery processing vulnerability Published: February 25, 2021 Latest version available from: https://w1.fi/security/2021-1/ Vulnerability A vulnerability was discovered in how wpa_supplicant processes P2P (Wi-Fi Direct) provision discovery requests. Under a corner case condition, an invalid Provision Discovery Request frame could end up reaching a state where the oldest peer entry needs to be removed. With a suitably constructed invalid frame, this could result in use (read+write) of freed memory. This can result in an attacker within radio range of the device running P2P discovery being able to cause unexpected behavior, including termination of the wpa_supplicant process and potentially code execution. Vulnerable versions/configurations wpa_supplicant v1.0-v2.9 with CONFIG_P2P build option enabled An attacker (or a system controlled by the attacker) needs to be within radio range of the vulnerable system to send a set of suitably constructed management frames that trigger the corner case to be reached in the management of the P2P peer table. Possible mitigation steps - Merge the following commit to wpa_supplicant and rebuild it: P2P: Fix a corner case in peer addition based on PD Request This patch is available from https://w1.fi/security/2021-1/ - Update to wpa_supplicant v2.10 or newer, once available - Disable P2P (control interface command “P2P_SET disabled 1” or “p2p_disabled=1” in (each, if multiple interfaces used) wpa_supplicant configuration file) - Disable P2P from the build (remove CONFIG_P2P=y)