#VU58858 Out-of-bounds read in macOS - CVE-2021-30939

Vulnerability identifier: #VU58858

Vulnerability risk: High

CVSSv4.0: 7.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/U:Amber]

CVE-ID: CVE-2021-30939

CWE-ID: CWE-125

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
macOS
Operating systems & Components / Operating system

Vendor: Apple Inc.

Description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a boundary error when processing DDS images in ImageIO. A remote attacker can create a specially crafted image file, trick the victim into opening it using the affected software, trigger out-of-bounds read error and execute arbitrary code on the target system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

macOS: 12.0 21A344 - 12.0.1 21A559

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External links
https://support.apple.com/en-us/HT212978
https://www.zerodayinitiative.com/advisories/ZDI-22-359/

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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. However, proof of concept for this vulnerability is available.