Description
A flaw was found in Samba’s vfs_worm module. The module is intended to provide write-once, read-many (WORM) protections by preventing modification of files after a configurable grace period. Due to insufficient validation during rename operations, an authenticated user with write access to a share could overwrite a protected file by renaming a newly created file over the existing WORM-protected file.
Problem types
Improper Handling of Insufficient Permissions or Privileges
Product status
0:4.23.5-109.el10_2 (rpm) before *
Timeline
| 2026-03-13: | Reported to Red Hat. |
| 2026-05-27: | Made public. |
Credits
Red Hat would like to thank Pavel Kohout (Aisle Research) for reporting this issue.
References
access.redhat.com/errata/RHSA-2026:22963 (RHSA-2026:22963)
access.redhat.com/security/cve/CVE-2026-2340
bugzilla.redhat.com/show_bug.cgi?id=2447318 (RHBZ#2447318)
bugzilla.samba.org/show_bug.cgi?id=15997