Description

Use after free in Windows LDAP - Lightweight Directory Access Protocol allows an unauthorized attacker to execute code over a network.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "8.8",
  "pubDate": "2026-08-11T17:18:33.390Z",
  "pubdate": "2026-08-11T17:18:33.390Z",
  "executiveSummary": "This vulnerability is classified as a use-after-free weakness affecting the Windows Lightweight Directory Access Protocol (LDAP) component. The flaw introduces significant security risks, potentially allowing an unauthorized network-based attacker to achieve remote code execution on vulnerable systems.\nThe executive impact of this vulnerability is severe, as successful exploitation could grant an attacker the ability to execute arbitrary code within the context of the service, leading to complete system compromise, unauthorized access to sensitive directory information, and potential lateral movement across the affected network.\nAffected systems include Windows operating systems utilizing the vulnerable LDAP implementation. The attack capabilities require network connectivity to the target service without necessarily requiring prior authentication, depending on the specific network configuration and exposure of the LDAP endpoints.\nExploitation requirements center on the ability to send specially crafted LDAP requests that trigger memory corruption through improper heap management. There are no additional preconditions specified beyond network reachability to the vulnerable Windows LDAP service.",
  "technicalDetails": "The root cause of the vulnerability stems from a memory management flaw specifically characterized as a use-after-free condition within the Windows Lightweight Directory Access Protocol (LDAP) subsystem. This memory corruption vulnerability occurs when the application fails to properly clear pointers to dynamically allocated memory after the memory has been freed.\nThe vulnerable component is the Windows LDAP protocol parser and handler, which processes incoming directory service requests. When processing specific sequences of malformed or maliciously crafted LDAP packets, the affected component improperly handles object lifecycles, leading to the premature release of memory while retaining dangling pointers.\nThe attack flow proceeds as an unauthorized attacker transmits crafted LDAP requests over the network to the targeted Windows system. Upon receiving the payload, the vulnerable LDAP service processes the requests, inadvertently referencing the dangling pointer to the previously freed memory location.\nBy carefully manipulating the heap state prior to or during the triggering condition—often referred to as heap grooming or spraying—an attacker can induce the reallocation of the freed memory chunk with controlled data, such as shellcode or malicious function pointers.\nWhen the application subsequently dereferences the dangling pointer, execution flow is redirected to the attacker-controlled data. This payload behavior facilitates arbitrary code execution with the privileges of the LDAP service process.\nAuthentication requirements are minimal, as the vulnerability can be leveraged by an unauthorized attacker over the network. Privilege requirements depend on the exposure of the network service, but successful exploitation typically compromises the security boundary of the underlying Windows service. Network exposure is broad for systems hosting publicly accessible or internally exposed LDAP endpoints. Post-exploitation impact includes full system compromise, escalation of privileges, and persistent unauthorized access to the directory environment."
}