An issue was discovered in Illumos in Nexenta NexentaStor 4.0.5 and 5.1.2, and other products. The SMB server allows an attacker to have unintended access, e.g., an attacker with WRITE_XATTR can change permissions. This occurs because of a combination of three factors: ZFS extended attributes are used to implement NT named streams, the SMB protocol requires implementations to have open handle semantics similar to those of NTFS, and the SMB server passes along certain attribute requests to the underlying object (i.e., they are not considered to be requests that pertain to the named stream).
Conclusion & alert: CVE-2019-9579 is rated Moderate Risk (57.8/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.73%).Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
Exploit prediction scoring system (EPSS) score for CVE-2019-9579
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).