Authenticated file-behavior modification via unchecked reparse operations
Published May 27, 2026 · Updated Aug 31, 2026
Improper access control in Samba 4.21 and later allows remote authenticated users to alter reparse metadata on read-only SMB shares. The SMB handlers set or delete user.SmbReparse and the reparse-point bit in user.DosAttrib without enforcing the share or handle read-only state. Exploitation requires SMB authentication and filesystem write permission; affected files can appear as symlinks or other reparse types, and broad conversion can temporarily deny normal access.
Summary
What happened
Improper access control in Samba 4.21 and later allows remote authenticated users to alter reparse metadata on read-only SMB shares. The SMB handlers set or delete user.SmbReparse and the reparse-point bit in user.DosAttrib without enforcing the share or handle read-only state. Exploitation requires SMB authentication and filesystem write permission; affected files can appear as symlinks or other reparse types, and broad conversion can temporarily deny normal access.
The record
- CVE
- CVE-2026-1933
- Published
- May 27, 2026
- Updated
- Aug 31, 2026
- Vendor
- 389 Directory Server
- Product
- Red Hat OpenShift Container Platform 4.16
- Classifications
- CWE-284, T1210
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- May 27, 2026CVE publishedPublication date reported by the CVE source.
- Aug 31, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo