RHSA-2026:28056HighCVSS 9.0

Red Hat Security Advisory: samba security update

Published
June 23, 2026
Last Modified
August 24, 2026

🔗 CVE IDs covered (5)

CVE-2026-1933 →CVE-2026-2340 →CVE-2026-3012 →CVE-2026-4408 →CVE-2026-4480 →

📋 Description

CVE-2026-1933 — samba: Missing access check on reparse point operations CVE-2026-2340 — samba: vfs_worm does not block directory modification CVE-2026-3012 — samba: group policy certificate enrollment uses http:// without validation CVE-2026-4408 — samba: Remote Code Execution in SAMR CVE-2026-4480 — samba: Samba: Remote Code Execution in printing subsystem via unescaped job description

🎯 Affected products200

  • Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • Red Hat Enterprise Linux AppStream TUS (v.8.8)
  • Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • Red Hat Enterprise Linux BaseOS TUS (v.8.8)
  • ctdb-0:4.17.5-7.el8_8.1.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • ctdb-0:4.17.5-7.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • ctdb-0:4.17.5-7.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
  • ctdb-debuginfo-0:4.17.5-7.el8_8.1.i686 as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • ctdb-debuginfo-0:4.17.5-7.el8_8.1.i686 as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
  • ctdb-debuginfo-0:4.17.5-7.el8_8.1.ppc64le as a component of Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • ctdb-debuginfo-0:4.17.5-7.el8_8.1.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • ctdb-debuginfo-0:4.17.5-7.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • ctdb-debuginfo-0:4.17.5-7.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux AppStream TUS (v.8.8)
  • ctdb-debuginfo-0:4.17.5-7.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • ctdb-debuginfo-0:4.17.5-7.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
  • libnetapi-0:4.17.5-7.el8_8.1.i686 as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • libnetapi-0:4.17.5-7.el8_8.1.i686 as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
  • libnetapi-0:4.17.5-7.el8_8.1.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • libnetapi-0:4.17.5-7.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • libnetapi-0:4.17.5-7.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
  • libnetapi-debuginfo-0:4.17.5-7.el8_8.1.i686 as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • libnetapi-debuginfo-0:4.17.5-7.el8_8.1.i686 as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
  • libnetapi-debuginfo-0:4.17.5-7.el8_8.1.ppc64le as a component of Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • libnetapi-debuginfo-0:4.17.5-7.el8_8.1.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • libnetapi-debuginfo-0:4.17.5-7.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • libnetapi-debuginfo-0:4.17.5-7.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux AppStream TUS (v.8.8)
  • libnetapi-debuginfo-0:4.17.5-7.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • libnetapi-debuginfo-0:4.17.5-7.el8_8.1.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
  • libsmbclient-0:4.17.5-7.el8_8.1.i686 as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • libsmbclient-0:4.17.5-7.el8_8.1.i686 as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
  • +170 more not shown

✅ Remediation

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 Workaround: Administrators can mitigate this issue by ensuring users who access a read only = yes Samba share do not have filesystem-level write permission to the exported files. A server administrator may also monitor and remove unintended "user.SmbReparse" xattr (extended attributes) and the associated FILE_ATTRIBUTE_REPARSE_POINT "user.DosAttrib" bit metadata if exploitation is suspected. Workaround: Administrators can mitigate this issue by: Setting read-only permissions on protected files at the underlying filesystem level will prevent modifications. Configuring ```worm:grace_period = 0``` (zero or less) in smb.conf will eliminate the writable grace period (will eliminate the window in which the rename can happen), understanding that this may impact workflows requiring multi-step file creation. Workaround: Systems are not affected unless Samba Group Policy processing and certificate auto-enrollment are explicitly enabled. Administrators can reduce exposure by: Avoiding unnecessary use of certificate auto-enrollment. Ensuring your "smb.conf" does not contain a line like ```apply group policies = yes```. If , group policy is not be enabled, the vulnerable code will not run. Intercepting the HTTP request requires some control over the local network or other devices to intercept or redirect traffic. Some network administrators might assess this as a low risk on their networks. Workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability. Workaround: Remove ```"%J"``` from the "print command" in ```smb.conf``` entry.

🔗 References (8)