CVE-2025-24063 Overview
CVE-2025-24063 is a heap-based buffer overflow vulnerability in the Microsoft Windows Kernel. An authorized local attacker can exploit the flaw to elevate privileges and execute code in the kernel context. The vulnerability affects a broad range of Windows client and server versions, from Windows 10 1507 through Windows 11 24H2, and from Windows Server 2008 through Windows Server 2025. Microsoft addressed the issue in the May 2025 security update cycle. The vulnerability is tracked under [CWE-122] (Heap-based Buffer Overflow) and [CWE-787] (Out-of-bounds Write).
Critical Impact
Successful exploitation grants SYSTEM-level privileges, allowing attackers to bypass user-mode security boundaries, disable endpoint protections, and persist on the host.
Affected Products
- Microsoft Windows 10 (1507, 1607, 1809, 21H2, 22H2) across x86, x64, and ARM64
- Microsoft Windows 11 (22H2, 23H2, 24H2) across x64 and ARM64
- Microsoft Windows Server 2008, 2012, 2016, 2019, 2022, 2022 23H2, and Server 2025
Discovery Timeline
- 2025-05-13 - CVE-2025-24063 published to the National Vulnerability Database
- 2025-05-19 - Last updated in NVD database
Technical Details for CVE-2025-24063
Vulnerability Analysis
The flaw resides in the Windows Kernel and is classified as a heap-based buffer overflow with an associated out-of-bounds write condition. When the kernel processes a specific request or input structure, it writes data beyond the bounds of an allocated heap buffer. This corruption occurs in non-paged kernel pool memory, where adjacent objects can include kernel structures used for access control decisions.
A local attacker with low-privilege authenticated access on the target host can trigger the vulnerable code path through a crafted system call or IOCTL interaction. The overflow allows the attacker to overwrite adjacent kernel objects, leading to arbitrary kernel write primitives. Chained with object replacement techniques, this enables full privilege escalation to NT AUTHORITY\SYSTEM.
Root Cause
The root cause is improper validation of input length or element count before writing user-controlled data into a fixed-size heap allocation. The kernel fails to enforce the boundary between the allocated size and the data being written, producing a classic [CWE-122] heap overflow that overlaps neighboring pool chunks.
Attack Vector
Exploitation requires local access and an authenticated user context. No user interaction beyond the attacker's own session is required. The attack vector is consistent with post-compromise scenarios, including malware seeking to escape sandboxes, abuse standard user footholds, or escalate from initial access via phishing or commodity loaders. Microsoft has not reported in-the-wild exploitation, and the vulnerability is not currently listed in the CISA Known Exploited Vulnerabilities catalog. The EPSS probability stands at 0.69 percent. Technical details on the precise vulnerable component are not disclosed in the public advisory. Refer to the Microsoft CVE-2025-24063 Advisory for additional information.
Detection Methods for CVE-2025-24063
Indicators of Compromise
- Unexpected SYSTEM-level processes spawned from standard user sessions or interactive logon contexts
- Kernel bug checks (BSOD) with stop codes related to pool corruption (BAD_POOL_HEADER, KERNEL_MODE_HEAP_CORRUPTION) on hosts missing the May 2025 update
- Loading of unsigned or unusual drivers immediately preceding privilege transitions
Detection Strategies
- Monitor for token manipulation patterns, including processes acquiring SYSTEM tokens without a legitimate parent service
- Correlate suspicious local process creations with subsequent kernel-mode telemetry such as driver loads or pool tag anomalies
- Hunt for known local privilege escalation tradecraft, including handle duplication from lsass.exe or services.exe initiated by non-administrative users
Monitoring Recommendations
- Enable kernel-mode auditing and forward Sysmon Event IDs 1, 10, and 11 to a centralized analytics platform
- Track patch deployment status across the fleet using configuration management tooling to confirm the May 2025 cumulative update is installed
- Establish alerting on Windows Event ID 4672 (special privileges assigned) for accounts that should never receive SeDebugPrivilege or SeLoadDriverPrivilege
How to Mitigate CVE-2025-24063
Immediate Actions Required
- Apply the May 2025 Microsoft security updates to all affected Windows client and server SKUs without delay
- Inventory legacy systems still on Windows Server 2008 or 2012 and confirm Extended Security Update (ESU) coverage is current
- Restrict local interactive logon rights to reduce the pool of accounts that could trigger the vulnerable code path
- Enforce application allowlisting to limit which binaries low-privilege users can execute on production systems
Patch Information
Microsoft released patches addressing CVE-2025-24063 in the May 2025 Patch Tuesday cycle. Updates are distributed through Windows Update, WSUS, and the Microsoft Update Catalog. Administrators should consult the Microsoft CVE-2025-24063 Advisory to identify the specific KB article applicable to each supported build.
Workarounds
- No vendor-supplied workaround is documented; patching remains the only complete remediation
- Reduce blast radius by removing local administrator rights from standard user accounts and enforcing least privilege
- Enable Credential Guard and Hypervisor-Protected Code Integrity (HVCI) where supported to raise the cost of kernel exploitation
# Verify the May 2025 cumulative update is installed (PowerShell)
Get-HotFix | Where-Object { $_.InstalledOn -ge (Get-Date '2025-05-13') } | Sort-Object InstalledOn -Descending
# Force a Windows Update scan and install pending security updates
UsoClient.exe StartScan
UsoClient.exe StartDownload
UsoClient.exe StartInstall
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
