CVE-2020-0674 is a remote code execution vulnerability in Microsoft Internet Explorer caused by memory corruption in the legacy JScript scripting engine. The flaw arises from improper handling of objects in memory, specifically a garbage-collection tracking failure involving named arguments in an Array.sort callback, which can lead to use-after-free conditions in jscript.dll. The issue affects scenarios where Internet Explorer renders content that invokes the legacy JScript engine rather than Jscript9.dll. An attacker can trigger the vulnerability by causing a target to load specially crafted web content, including through a malicious or compromised website, or through an application or Microsoft Office document that hosts the Internet Explorer rendering engine via a safe-for-initialization ActiveX control. Microsoft addressed the vulnerability by modifying how the scripting engine handles objects in memory.
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1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos (2 hidden).
This repository contains a working exploit for CVE-2020-0674, a use-after-free vulnerability in the legacy JScript engine of Internet Explorer. The exploit is implemented as a single HTML file (exploit.html) containing heavily commented JScript code. The exploit targets 64-bit versions of Internet Explorer (8, 9, 10, 11) on Windows 7, and leverages a flaw in the Array.sort comparator function to achieve arbitrary code execution. The provided payload launches the Windows calculator (calc.exe) to demonstrate successful exploitation, but the payload can be modified for arbitrary command execution. The README.md provides detailed background, configuration requirements, and usage notes. The exploit does not fully bypass all EMET mitigations but works under certain configurations. The main attack vector is through a malicious web page viewed in a vulnerable version of Internet Explorer. Notable fingerprintable endpoints include the path to calc.exe and the TabProcGrowth registry key, which is relevant for enabling the x64 process required for exploitation.
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22 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
An Internet Explorer 0-day and variant/misfix-related vulnerability from the same jscript bug class as CVE-2019-1367, exploited in the wild by DarkHotel APT.
Referenced only in an informational update note as another CVE issued to address the vulnerability; no technical details are provided in the content.
An Internet Explorer remote code execution vulnerability previously added to Purple Fox's arsenal and referenced here as an initial access vector.
An Internet Explorer remote code execution vulnerability exploited by DarkHotel in a campaign targeting Chinese government agencies and used to deliver Gh0st RAT.
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Every observed campaign linking this CVE to a named adversary.
Malware families riding this exploit, with evidence and IOCs.
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Cross-references every affected SKU, including bundled OEM variants.
Community discussion across Reddit, Mastodon, and other social sources.