Vulnerability Spotlight: Code execution vulnerability in Microsoft Excel

Summary: Cisco Talos discovered a use-after-free code execution vulnerability in Microsoft Excel, tracked as TALOS-2020-1153/CVE-2020-17123, that an attacker triggers by tricking a victim into opening a specially crafted XLS file. Talos confirmed the flaw affects Microsoft Office 365 ProPlus x86, version 2002, build 12527.20988, and Microsoft disclosed and patched it in its monthly security update.
Bottom line: Exploitation requires only that a user open a malformed XLS file, so a single document delivered to one Excel user on the confirmed build is enough to hand an attacker remote code execution on that machine.

Read the original at Cisco Talos ↗

Topics: Vulnerabilities & Patching
Mentions: CVE-2020-17123
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