Vulnerability Spotlight: Information disclosure vulnerability in macOS SMB server

Summary: Cisco Talos discovered an integer overflow vulnerability, TALOS-2021-1237 (CVE-2021-1878), in Apple macOS's proprietary SMB server, in the way it processes SMB3 compounded packets. An attacker could send a specially crafted packet to view sensitive information, bypass cryptographic checks, and cause a denial of service; Apple has released an update, and Talos confirmed macOS 11.1 could be exploited.
What's compelling: A single crafted packet against the SMB server can expose sensitive information and slip past cryptographic checks, so any Mac still on 11.1 carries that exposure until it is updated.

Read the original at Cisco Talos ↗

Topics: Endpoint & Network Security
Mentions: CVE-2021-1878
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