Description

Stack-based buffer overflow in Windows DHCP Client allows an authorized attacker to elevate privileges locally.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.8",
  "pubDate": "2026-08-11T17:18:28.260Z",
  "pubdate": "2026-08-11T17:18:28.260Z",
  "executiveSummary": "A stack-based buffer overflow vulnerability exists within the Windows DHCP Client, affecting local system security posture.\nThe vulnerability allows an authorized local attacker to execute arbitrary code and achieve local privilege escalation by manipulating memory structures within the vulnerable component.\nAffected systems are limited to the Windows operating systems utilizing the vulnerable DHCP Client implementation.\nThe risk implication is severe, as successful exploitation grants the attacker elevated privileges, potentially compromising the entire underlying operating system.\nPrerequisites for this attack require the adversary to possess local execution capabilities and authorization to interact with the targeted system.\nMitigation requires applying vendor-supplied security updates specifically addressing the memory corruption flaw within the DHCP Client service.",
  "technicalDetails": "The vulnerability is fundamentally classified as a stack-based buffer overflow residing in the Windows DHCP Client.\nThe root cause stems from improper boundary checking and insufficient validation of input data processed by the vulnerable component during Dynamic Host Configuration Protocol lease acquisition or renewal operations.\nThe vulnerable component handles network configuration data without enforcing strict length constraints on incoming parameters, leading to uncontrolled memory copying into a fixed-size stack buffer.\nTo initiate the attack flow, an authorized local attacker leverages local access to supply malformed or excessively large input payloads designed to overflow the targeted stack-based buffer.\nAs the input is processed, the data exceeds the allocated stack space, overwriting adjacent stack memory structures, including saved frame pointers and return addresses.\nUpon function return, the instruction pointer is redirected to attacker-controlled memory containing shellcode or a malicious payload.\nBecause the Windows DHCP Client executes with high privileges, successful control flow hijacking results in the immediate execution of arbitrary code within the context of NT AUTHORITY\\SYSTEM.\nAuthentication requirements dictate that the attacker must possess local access and necessary authorization levels to trigger the vulnerable code path.\nThe attack is localized to the affected machine, meaning network exposure is restricted to the local execution boundary rather than remote vector exploitability.\nPost-exploitation impact includes complete system compromise, unauthorized modification of system resources, installation of persistent backdoors, and total circumvention of operating system access controls."
}