#VU58686 Out-of-bounds read in Apple iOS and iPadOS - CVE-2021-30831

Vulnerability identifier: #VU58686

Vulnerability risk: Medium

CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-30831

CWE-ID: CWE-125

Exploitation vector: 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 gain access to potentially sensitive information.

The vulnerability exists due to a boundary condition in the FontParser subsystem. A remote attacker can trick the victim to open a specially crafted website or document, trigger an out-of-bounds read error and read contents of memory on the system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Apple iOS: 14.0 18A373 - 14.0.1 18A393, 14.1 18A8395, 14.2 18B92 - 14.2.1 18B121, 14.3 18C66, 14.4 18D52 - 14.4.2 18D70, 14.5 18E199 - 14.5.1 18E212, 14.6 18F72, 14.7 18G69 - 14.7.1 18G82, 14.8 18H17

iPadOS: 14.0 18A373 - 14.8 18H17

---

External links
https://support.apple.com/en-us/HT212814

---

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.