Description

Stack-based buffer overflow in Windows TCP/IP allows an unauthorized attacker to execute code over a network.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "8.1",
  "pubDate": "2026-08-11T17:18:32.970Z",
  "pubdate": "2026-08-11T17:18:32.970Z",
  "executiveSummary": "A stack-based buffer overflow vulnerability has been identified within the Windows TCP/IP protocol stack. This critical security flaw allows an unauthorized remote attacker to achieve arbitrary code execution over a network without requiring any prior authentication or user interaction.\nThe vulnerability resides in the core network packet processing mechanics of the affected Windows operating systems. When maliciously crafted TCP/IP packets are transmitted to a vulnerable target, the underlying network driver fails to properly validate the size and boundaries of input data before writing it to a fixed-size stack buffer. This results in memory corruption, specifically overwriting adjacent stack memory structures, including return addresses and critical function pointers.\nThe risk implications are severe, as successful exploitation grants the adversary the ability to execute arbitrary native code within the context of the affected kernel or system service. This enables complete system compromise, unauthorized data access, lateral movement across the enterprise network, and the potential deployment of persistent malware.\nGiven that the attack vector is network-based and exploitable by unauthenticated threat actors, the vulnerability represents a high-severity threat to enterprise environments utilizing unpatched Windows infrastructure. Remediation requires the immediate application of vendor-supplied security updates and the enforcement of strict network perimeter controls.",
  "technicalDetails": "The vulnerability is classified as a classic stack-based buffer overflow stemming from improper bounds checking within the Windows TCP/IP protocol driver. The vulnerable component is responsible for parsing incoming network traffic, specifically handling incoming TCP/IP segments that contain malformed or excessively sized header parameters or payload data.\nThe root cause lies in insecure memory handling operations where the parsing function accepts variable-length network input and copies it into a statically allocated stack buffer via memory copy primitives (such as memcpy or custom byte-shifting loops) without accurately verifying that the destination buffer has sufficient capacity to hold the incoming data stream.\nThe exploitation method relies on transmitting a specifically crafted sequence of TCP/IP packets designed to exceed the byte allocation limit of the vulnerable stack buffer. As the input data is processed and written into memory, the overflowing bytes sequentially overwrite adjacent stack frames. By carefully crafting the payload, an attacker can overwrite the saved instruction pointer (RIP/EIP) with a controlled memory address pointing to shellcode or leveraging Return-Oriented Programming (ROP) gadget chains to bypass modern exploit mitigations like Data Execution Prevention (DEP) and Address Space Layout Randomization (ASLR).\nThe attack flow proceeds as follows: First, the unauthorized attacker establishes network connectivity to a vulnerable Windows system hosting the TCP/IP stack. Second, the attacker transmits the crafted network packets targeting the specific network processing routines. Third, the kernel-level driver parses the packet, triggering the out-of-bounds write condition on the stack. Fourth, upon function return, the instruction pointer is redirected to the attacker-supplied payload, executing malicious code with high-privilege kernel execution context.\nThe affected product is the Windows TCP/IP stack across applicable Microsoft Windows operating system versions. The vulnerability requires network exposure, meaning any system with network interfaces reachable by the attacker is potentially vulnerable. No user interaction or local authentication is necessary to trigger the flaw, making it highly attractive for automated worm propagation and remote exploitation scenarios."
}