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MediumExploited in the wildPublic exploit

Windows Boot Manager Secure Boot Security Feature Bypass

IdentifiersCVE-2023-24932CWE-693

CVE-2023-24932 is a security feature bypass vulnerability in Microsoft Windows Boot Manager that can be used to circumvent UEFI Secure Boot protections. The issue is associated with the BlackLotus UEFI bootkit and was addressed by Microsoft in May 2023. The provided content indicates the flaw affects the Windows boot chain by allowing use of an unsecured or vulnerable boot path so that untrusted software can execute during the boot process before the operating system fully loads. Microsoft’s remediation guidance for this issue includes not only patching the underlying flaw but also managing Windows Boot Manager revocations and Secure Boot DBX updates to prevent rollback to still-trusted vulnerable boot components.

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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 undermines Secure Boot’s trust guarantees and permits execution of untrusted code in the early boot process at the firmware/boot-manager stage. This can enable deployment of UEFI bootkits such as BlackLotus, persistence that may survive operating system reinstallation, and pre-OS tampering with platform security controls. The content also notes that bootkit activity in this context can facilitate disabling or bypassing protections before Windows loads, materially increasing stealth and persistence.

Mitigation

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

If full remediation cannot be completed immediately, reduce exposure by ensuring systems are fully updated, verifying Secure Boot is enabled and properly configured, updating bootable/recovery media, and applying available optional Secure Boot protections and revocations where supported. The content also reflects NSA/Microsoft guidance to actively manage UEFI Secure Boot configuration, monitor firmware and boot integrity, and where feasible customize Secure Boot policy to block older vulnerable Windows boot loaders. Devices unable to accept updated certificates or revocations should be tracked as exceptions and protected with compensating controls until replacement or full remediation is possible.

Remediation

Patch, then assume compromise.

Apply Microsoft’s May 2023 security updates for CVE-2023-24932 and follow Microsoft’s documented post-patch Secure Boot hardening steps. The content specifically references Microsoft guidance on managing Windows Boot Manager revocations for Secure Boot changes associated with CVE-2023-24932. Full remediation requires updating affected boot components and applying the relevant Secure Boot revocations/DBX updates so vulnerable older boot managers and bootloaders can no longer be trusted or rolled back to. Because incorrect revocation handling can render systems unbootable, remediation should be performed in accordance with Microsoft’s staged guidance and validated across firmware/OEM combinations.
PUBLIC EXPLOITS

Exploits

No valid public exploits. Mallory filtered out 3 candidates as fakes, detection scripts, or README-only repos.

VALID 0 / 3 TOTALView more in app

All candidate exploits were filtered out by Mallory's validation.

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 20h2operating_system
Microsoft CorporationWindows 10 21h2operating_system
Microsoft CorporationWindows 10 22h2operating_system
Microsoft CorporationWindows 11 21h2operating_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 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

Query your assets running an affected version, and investigate the blast radius.

Threat actor evidence7

Every observed campaign linking this CVE to a named adversary.

Associated malware16

Malware families riding this exploit, with evidence and IOCs.

Detection signatures

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 activity5

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