CVE-2025-24990 — Windows Untrusted Pointer Dereference (EoP)

Research writeup by Sentinel AI Defense. Defensive analysis only — no working exploit or PoC is published here.

A privileged Windows component dereferences a pointer it receives from an untrusted context without validating it — giving a low-privileged attacker arbitrary memory access and a reliable path to SYSTEM. Exploited in the wild in 2025.

📄 Full writeup: https://sentinelaidefense.com/posts/cve-2025-24990-windows-untrusted-pointer.html

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Overview

CVE-2025-24990 is an untrusted pointer dereference vulnerability in Microsoft Windows. It allows an attacker to escalate privileges or execute arbitrary code by exploiting improper validation of pointers received from untrusted sources.

The flaw was actively exploited in the wild in 2025 and added to the CISA KEV catalog. It is often used in local privilege escalation scenarios and can be chained with other vulnerabilities for broader impact. Patched by Microsoft in 2025 security updates.

Affected Versions

Affects various editions of:

• Windows 10
• Windows 11
• Windows Server (2016–2025 builds)

The vulnerability typically resides in core Windows components (kernel or system services) that handle untrusted input.

Technical Breakdown (Root Cause)

The root cause is improper validation of a pointer passed from user mode or another untrusted context to a higher-privileged component (e.g., kernel). When the system dereferences this pointer without adequate checks, an attacker can control memory access, leading to arbitrary read/write primitives or direct code execution in elevated context.

This class of bug (untrusted pointer dereference) is a common source of privilege escalation and information disclosure in Windows.

Attack Chain

1. Attacker gains initial code execution at a low privilege level (e.g., via phishing, malicious document, or existing foothold).
2. Triggers the vulnerability by passing a crafted pointer to the vulnerable component.
3. Achieves arbitrary memory access or code execution at a higher privilege level (often SYSTEM).
4. Performs further actions: credential dumping, lateral movement, or ransomware deployment.

It is frequently chained with browser or application exploits for full system compromise.

Detection Guidance

• Monitor Windows security logs for suspicious privilege escalation events or unusual kernel-mode activity.
• Look for crashes or anomalies in system processes related to pointer handling.
• EDR tools should flag rapid sequences of memory operations or attempts to access kernel structures from user mode.
• Behavioral indicators: unexpected SYSTEM-level process creation following user-mode activity.

Indicators of Compromise

• Specific exploit patterns targeting the vulnerable Windows component (often observed in exploit kits).
• Post-exploitation artifacts: LSASS dumps, new privileged accounts, or unusual driver loading.
• Hashes of known exploit tools or payloads associated with 2025 campaigns.

Mitigation

• Install Microsoft security updates from 2025 (particularly those addressing this CVE).
• Enable advanced Windows mitigations such as HVCI (Hypervisor-protected Code Integrity), Credential Guard, and Kernel Data Protection.
• Use least-privilege principles and application control (e.g., AppLocker or WDAC).
• Keep EDR solutions up to date with behavior-based rules for privilege escalation.

This vulnerability underscores the importance of timely patching and modern Windows security features, as untrusted pointer issues remain a reliable vector for attackers seeking SYSTEM access.

References

• Microsoft MSRC advisory for CVE-2025-24990
• NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-24990
• CISA Known Exploited Vulnerabilities Catalog

Disclaimer

This repository is published for defensive and educational purposes only. It contains analysis, detection logic, and mitigation guidance. No functional exploit code is provided. Use this information only on systems you are authorized to test and defend.

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_{Maintained by Sentinel AI Defense · Findings shared responsibly under coordinated disclosure.}