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HighCISA KEVExploited in the wildPublic exploit

Microsoft Scripting Engine Type Confusion RCE

IdentifiersCVE-2025-30397CWE-843· Access of Resource Using…

CVE-2025-30397 is a remote code execution vulnerability in the Microsoft Scripting Engine caused by access of a resource using an incompatible type (type confusion), leading to memory corruption. Microsoft describes the issue as affecting the Scripting Engine and allowing an unauthorized attacker to execute code over a network. Multiple sources in the provided content state exploitation occurs when malicious web content is rendered through Microsoft Edge running in Internet Explorer Mode, which still invokes legacy MSHTML/Trident scripting components. Successful exploitation requires luring a user into clicking a specially crafted link or visiting attacker-controlled web content, after which the type confusion condition can be triggered in the scripting engine and leveraged for arbitrary code execution. Microsoft reported the vulnerability as actively exploited in the wild at disclosure time.

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation allows remote arbitrary code execution in the context of the targeted user. This can give an attacker unauthorized control over the affected system sufficient to run malicious payloads, install malware, steal credentials or other data, and potentially deploy follow-on tooling such as ransomware. Because the flaw is network-deliverable through crafted web content but depends on user interaction and IE Mode, the practical impact is highest in environments that still rely on Edge Internet Explorer Mode for legacy applications.

Mitigation

If you can’t patch tonight, do this now.

If immediate patching is not possible, reduce exposure by disabling or restricting Microsoft Edge Internet Explorer Mode where operationally feasible, and migrate legacy applications away from IE-dependent rendering paths. Limit user exposure to untrusted links and web content through phishing-resistant controls, web filtering, and user awareness measures. Monitor endpoints for anomalous process creation and suspicious memory-access behavior associated with browser or scripting-engine exploitation, and use EDR/behavioral detections to identify exploitation attempts. Where business requirements permit, remove or tightly control legacy IE compatibility settings.

Remediation

Patch, then assume compromise.

Apply Microsoft's May 2025 security updates for affected Windows platforms. The provided content specifically references KB5058405 for Windows 10 and KB5058411 for Windows 11 as fixes for this vulnerability. Organizations should prioritize patching systems where Microsoft Edge Internet Explorer Mode is enabled or required for legacy application compatibility. Standard remediation is to deploy the relevant cumulative security updates from Microsoft across affected endpoints and servers.
PUBLIC EXPLOITS

Exploits

2 valid exploits after Mallory filtered fakes, detection scripts, and README-only repos (2 hidden).

VALID 2 / 4 TOTALView more in app
CVE-2025-30397---Windows-Server-2025-JScript-RCE-Use-After-Free-MaturityPoCVerified exploit

This repository provides a proof-of-concept (PoC) exploit for CVE-2025-30397, a critical Use-After-Free vulnerability in the JScript engine (jscript.dll) affecting Windows Server 2025 (build 25398 and prior) when accessed via Internet Explorer 11. The repository consists of three files: a LICENSE, a README.md with technical and usage details, and the main exploit script (exploit.py). The exploit.py script implements a simple Python HTTP server that serves a malicious HTML page containing heap-spraying JavaScript and shellcode. When a vulnerable system visits the provided URL (http://<attacker-ip>:8080/poc_cve_2025_30397.html) using IE11, the exploit triggers the vulnerability, resulting in remote code execution (demonstrated by launching calc.exe). The exploit is a functional PoC, not weaponized, and is intended for ethical testing and research. No hardcoded IPs or domains are present; the attacker must provide their own IP address when serving the exploit.

mbanyamerDisclosed May 31, 2025pythonhtmlbrowsernetwork
ChromSploit-FrameworkMaturityPoCFrameworkChromSploit FrameworkVerified exploit

ChromSploit Framework is a modular, extensible exploitation and research platform focused on browser and server vulnerabilities. It provides operational exploit modules for several high-profile CVEs (including Chrome, Edge, Firefox, Tomcat, and Git), with a strong emphasis on safety: all exploits default to simulation mode, and real exploitation requires explicit authorization. The framework supports multi-stage browser exploit chains, advanced payload obfuscation, automated tunneling (ngrok), and C2 integration (Sliver, Metasploit). It includes a professional reporting system, live monitoring, and evidence collection. The repository is well-structured, with clear separation between core logic, modules, exploits, and documentation. Numerous endpoints are fingerprintable, including local HTTP servers for exploit delivery, OAuth phishing, and data exfiltration. The codebase is primarily Python, with supporting JavaScript, JSP, and shell scripts. This framework is suitable for advanced security research, red teaming, and educational demonstrations, but should only be used in authorized, isolated environments due to the presence of real exploit code (even though simulation is the default).

Leviticus-TriageDisclosed May 26, 2025pythonjavascriptbrowsernetworklocal
EXPOSURE SURFACE

Affected products & vendors

Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.

VendorProductType
Microsoft CorporationWindows 10 1507operating_system
Microsoft CorporationWindows 10 1607operating_system
Microsoft CorporationWindows 10 1809operating_system
Microsoft CorporationWindows 10 21h2operating_system
Microsoft CorporationWindows 10 22h2operating_system
Microsoft CorporationWindows 11 22h2operating_system
Microsoft CorporationWindows 11 23h2operating_system
Microsoft CorporationWindows 11 24h2operating_system
Microsoft CorporationWindows Server 2008operating_system
Microsoft CorporationWindows Server 2008 R2operating_system
Microsoft CorporationWindows Server 2008 Sp2operating_system
Microsoft CorporationWindows Server 2012operating_system
Microsoft CorporationWindows Server 2012 R2operating_system
Microsoft CorporationWindows Server 2016operating_system
Microsoft CorporationWindows Server 2019operating_system
Microsoft CorporationWindows Server 2022operating_system
Microsoft CorporationWindows Server 2022 23h2operating_system
Microsoft CorporationWindows Server 2025operating_system
Microsoft CorporationWindows Server 23h2operating_system

Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.

What this page doesn’t show

The version that knows your environment.

This page is what’s public. Mallory adds the parts that aren’t: which of your assets are affected, which adversaries are exploiting it right now, which detections to deploy, and what to do tonight.
Exposure mapping

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Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware

Malware families riding this exploit, with evidence and IOCs.

Detection signatures2

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity18

Community discussion across Reddit, Mastodon, and other social sources.