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HighCISA KEVExploited in the wildPublic exploit

Win32k.sys Elevation of Privilege Vulnerability

IdentifiersCVE-2015-1701CWE-269

CVE-2015-1701 is a local elevation-of-privilege vulnerability in the Win32k.sys kernel-mode driver on Microsoft Windows Server 2003 SP2, Windows Vista SP2, and Windows Server 2008 SP2. The issue allows a locally authenticated attacker to run a crafted application that abuses flawed handling in the Win32k subsystem to obtain elevated privileges. Microsoft described it as a Windows Kernel-Mode Drivers / Win32k Elevation of Privilege Vulnerability and patched it in MS15-051. Reporting in the provided content indicates the flaw was exploited in the wild in April 2015 and was used by APT28/Sednit and other actors as a post-compromise privilege-escalation step. The supporting material further notes operational use of the vulnerability to access the SYSTEM token and copy it into the current process, indicating exploitation results in execution under Local System or equivalent highly privileged context.

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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 a local user to elevate privileges from a lower-privileged account to SYSTEM. In observed intrusions, attackers used the vulnerability to obtain the SYSTEM token and duplicate or copy it into the current process, enabling full control over the affected host. This level of access permits disabling or bypassing security controls, dumping credentials, installing persistent malware, loading additional payloads, modifying protected files and registry locations, and using the compromised system as a higher-trust foothold for further intrusion activity.

Mitigation

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

Because this is a local privilege-escalation flaw, mitigation centers on reducing opportunities for local code execution and limiting post-compromise abuse. Restrict interactive logon and code execution for untrusted users, enforce application allowlisting, and prevent execution from user-writable locations where feasible. Use least-privilege account assignments, monitor for suspicious token manipulation and SYSTEM-token theft behavior, and detect exploitation chains involving Office/Flash/browser initial access followed by local privilege escalation. Network-facing mitigations alone are insufficient because exploitation requires local execution on the target host.

Remediation

Patch, then assume compromise.

Apply Microsoft security update MS15-051, which addresses CVE-2015-1701 in Windows kernel-mode drivers / Win32k.sys. Prioritize patching affected legacy platforms identified in the content: Windows Server 2003 SP2, Windows Vista SP2, and Windows Server 2008 SP2. More broadly, remove or upgrade unsupported Windows versions where possible, as these platforms are high-risk for post-compromise local privilege escalation. Validate that all systems have the May 2015 Microsoft security updates or later cumulative/security rollups that supersede MS15-051.
PUBLIC EXPLOITS

Exploits

1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos (1 hidden).

VALID 1 / 2 TOTALView more in app
CVE-2015-1701MaturityPoCVerified exploit

This repository contains a functional local privilege escalation exploit for CVE-2015-1701, a vulnerability in the Microsoft Windows kernel (win32k.sys) that allows a local user to elevate privileges to SYSTEM. The exploit is implemented in C and is structured as a Visual Studio project, with the main logic in 'Source/Taihou/main.c'. Supporting files provide minimal runtime library functions. The exploit works by manipulating kernel structures and function pointers to steal the SYSTEM process token and assign it to the current process. Upon success, it spawns a SYSTEM-level command prompt (cmd.exe). The exploit only works on unpatched systems (Windows build <= 7601, prior to MS15-051). No network or remote attack vector is present; exploitation requires local code execution. The repository is well-structured, with clear separation between exploit logic and utility functions.

hfiref0xDisclosed May 12, 2015clocal
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 2003 Serveroperating_system
Microsoft CorporationWindows 7operating_system
Microsoft CorporationWindows Server 2008operating_system
Microsoft CorporationWindows Vistaoperating_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 evidence8

Every observed campaign linking this CVE to a named adversary.

Associated malware3

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 activity

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