#VU54949 Format string error in Apple iOS and iPadOS


Published: 2021-07-19 | Updated: 2021-07-22

Vulnerability identifier: #VU54949

Vulnerability risk: High

CVSSv3.1: 7.9 [CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C]

CVE-ID: CVE-2021-30800

CWE-ID: CWE-134

Exploitation vector: Local network

Exploit availability: No

Vulnerable software:
Apple iOS
Operating systems & Components / Operating system
iPadOS
Operating systems & Components / Operating system

Vendor: Apple Inc.

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a format string error in the wifid daemon when processing SSID name while connecting to a Wi-Fi hotspot. A remote attacker can supply a specially crafted SSID name that contains format string specifiers and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Apple iOS: 14.5 18E199 - 14.5.1 18E212, 14.2 18B92 - 14.2.1 18B121, 14.0 18A373 - 14.0.1 18A393, 14.4 18D52 - 14.4.2 18D70

iPadOS: 14.0 18A373 - 14.6 18F72


External links
http://blog.zecops.com/research/meet-wifidemon-ios-wifi-rce-0-day-vulnerability-and-a-zero-click-vulnerability-that-was-silently-patched/
http://www.bleepingcomputer.com/news/security/iphone-bug-breaks-wifi-when-you-join-hotspot-with-unusual-name/
http://blog.chichou.me/2021/06/20/quick-analysis-wifid/
http://support.apple.com/en-us/HT212601


Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.


Latest bulletins with this vulnerability