Back Linuxsecurity Ubuntu 26.04 LTS Samba Critical Update Denial of Service USN-8306
A security issue affects these releases of Ubuntu and its derivatives: - Ubuntu 26.04 LTS - Ubuntu 25.10 - Ubuntu 24.04 LTS - Ubuntu 22.04 LTS Summary: Several security issues were fixed in Samba. Software Description: - samba: SMB/CIFS file, print, and login server for Unix Details: Asim Viladi Oglu Manizada discovered that Samba incorrectly handled access checks on reparse point operations. An attacker could possibly use this issue to modify reparse point extended attributes on files that should have been read-only. This issue only affected Ubuntu 25.10 and Ubuntu 26.04 LTS. (CVE-2026-1933) Pavel Kohout discovered that Samba's vfs_worm module did not properly block file overwrites. An attacker could possibly use this issue to overwrite files that should have remained immutable. (CVE-2026-2340) Arad Inbar, Nir Somech, and Ben Grinberg discovered that Samba incorrectly handled certificate auto-enrolment group policies over HTTP without verification. A machine-in-the-middle ...
The problem can be corrected by updating your system to the following package versions: Ubuntu 26.04 LTS samba 2:4.23.6+dfsg-1ubuntu2.1 Ubuntu 25.10 samba 2:4.22.3+dfsg-4ubuntu2.4 Ubuntu 24.04 LTS samba 2:4.19.5+dfsg-4ubuntu9.6 Ubuntu 22.04 LTS samba 2:4.15.13+dfsg-0ubuntu1.12 In general, a standard system update will make all the necessary changes.
CVE-2026-1933, CVE-2026-2340, CVE-2026-3012, CVE-2026-3238,
Ubuntu Security Notice USN-8306-1
Get the latest Linux and open source security news straight to your inbox.
The full story
This article is one source in a clustered incident — the cluster page carries the summary, timeline and every other outlet covering it.
