Description

Relative path traversal in .NET Framework allows an unauthorized attacker to elevate privileges locally.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.8",
  "pubDate": "2026-08-11T17:19:00.570Z",
  "pubdate": "2026-08-11T17:19:00.570Z",
  "executiveSummary": "This security assessment evaluates a relative path traversal vulnerability residing within the .NET Framework, which enables an unauthorized local attacker to successfully elevate privileges on the target system.\nThe vulnerability type is classified as a relative path traversal flaw, impacting the .NET Framework product ecosystem.\nSuccessful exploitation of this security defect allows a local threat actor to execute arbitrary operations or manipulate file system resources outside of intended permission boundaries, directly leading to a local privilege escalation scenario.\nThe risk implications are severe, as unauthorized elevation of privileges within a core software framework can compromise the integrity and security posture of the entire host operating system and dependent applications.\nAttacker capabilities require local execution access to the targeted machine to manipulate file paths and trigger the traversal condition.\nExploitation requirements rely on the presence of vulnerable .NET Framework components that fail to adequately sanitize relative path inputs, allowing malicious directory navigation sequences to be processed by the underlying system.",
  "technicalDetails": "The root cause of this vulnerability stems from insufficient validation and sanitization of relative path inputs within the affected .NET Framework component.\nWhen user-supplied or untrusted file paths containing relative traversal sequences, such as dot-dot-slash patterns, are processed by the framework, the underlying input validation mechanism fails to restrict file system access to the designated secure directory.\nThis implementation flaw permits an adversary to traverse outside the intended operational scope and interact with sensitive system resources or execute unauthorized file read and write operations.\nThe attack flow begins with an unauthorized local attacker identifying an entry point or API within the .NET Framework that improperly handles file paths.\nThe attacker then crafts a malicious payload incorporating relative path traversal sequences designed to target restricted system directories or configuration files.\nUpon submission of the maliciously crafted path to the vulnerable component, the .NET Framework resolves the path incorrectly, granting access to objects outside the intended security context.\nThe vulnerable component involves file system handling routines and path resolution functions within the .NET Framework.\nAuthentication requirements are minimal or non-existent locally, as the attacker leverages existing low-privileged access to interact with the vulnerable subsystem.\nPrivilege requirements are restricted to local access, meaning the adversary must already possess the ability to execute code locally on the target system before initiating the path traversal attack.\nNetwork exposure is low, as the attack vector is strictly local and cannot be exploited remotely without an intermediary local execution mechanism.\nThe payload behavior involves the manipulation of file paths to access, modify, or plant files in privileged locations, which can subsequently be leveraged to hijack control flows, execute malicious binaries with elevated permissions, or compromise system integrity.\nThe post-exploitation impact results in a definitive local privilege escalation, allowing the attacker to bypass access controls, escalate privileges from a standard user to a highly privileged context, and achieve complete control over the affected environment."
}