CVE-2022-3592 in Samba
Summary
by MITRE • 01/12/2023
A symlink following vulnerability was found in Samba, where a user can create a symbolic link that will make 'smbd' escape the configured share path. This flaw allows a remote user with access to the exported part of the file system under a share via SMB1 unix extensions or NFS to create symlinks to files outside the 'smbd' configured share path and gain access to another restricted server's filesystem.
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Analysis
by VulDB Data Team • 04/08/2025
The vulnerability identified as CVE-2022-3592 represents a critical symlink following flaw within the Samba file sharing implementation that fundamentally compromises the security boundaries designed to protect networked file systems. This issue specifically affects the smbd daemon which serves as the primary SMB/CIFS server component in Samba installations, creating a pathway for unauthorized access that bypasses configured share restrictions through improper handling of symbolic links. The flaw exists in the way the daemon processes symbolic links within shared directories, allowing malicious actors to manipulate file system traversal mechanisms to escape designated share boundaries.
The technical implementation of this vulnerability stems from inadequate validation of symbolic link targets within the SMB protocol handling mechanisms, particularly when utilizing SMB1 unix extensions or NFS protocols that provide extended file system access capabilities. When a user creates a symbolic link pointing to a location outside the configured share path, the smbd daemon fails to properly enforce access controls that should prevent such traversal operations. This behavior directly violates the principle of least privilege and allows attackers to navigate beyond the intended file system boundaries, potentially accessing sensitive data, system files, or other restricted resources that should remain isolated within their designated share contexts. The vulnerability manifests when the daemon follows symbolic links without proper path validation, creating a privilege escalation scenario where file system access is extended beyond the original share configuration.
From an operational impact perspective, this vulnerability presents a severe risk to organizations relying on Samba for network file sharing services, as it enables remote attackers to gain unauthorized access to restricted file systems without requiring elevated privileges or authentication credentials beyond basic SMB access. The attack surface expands significantly since any user with access to the exported share can potentially exploit this flaw to access other server filesystems, creating a potential for data exfiltration, system compromise, or further lateral movement within the network infrastructure. This vulnerability particularly affects environments where Samba serves multiple shares with different access controls, as it undermines the fundamental security model that isolates different share contexts from each other.
The remediation approach for CVE-2022-3592 requires immediate implementation of security patches provided by Samba developers, as well as configuration adjustments to disable problematic protocol extensions when not essential for operations. Organizations should consider implementing additional monitoring for symbolic link creation within shared directories and establishing more restrictive access controls for SMB shares. The vulnerability aligns with CWE-59, which specifically addresses improper handling of symbolic links, and represents a classic example of path traversal vulnerability that can be exploited through protocol extensions. From an ATT&CK framework perspective, this vulnerability maps to techniques involving privilege escalation and lateral movement, as attackers can leverage the flaw to access resources they would not normally have access to, potentially leading to further compromise of the affected systems and network infrastructure.