1.2 Low
CVSS2
Attack Vector
LOCAL
Attack Complexity
HIGH
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
PARTIAL
Availability Impact
NONE
AV:L/AC:H/Au:N/C:N/I:P/A:N
2.5 Low
CVSS3
Attack Vector
LOCAL
Attack Complexity
HIGH
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
LOW
Availability Impact
NONE
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N
0.001 Low
EPSS
Percentile
44.9%
All versions of Samba prior to 4.13.16 are vulnerable to a malicious client using an SMB1 or NFS race to allow a directory to be created in an area of the server file system not exported under the share definition. Note that SMB1 has to be enabled, or the share also available via NFS in order for this attack to succeed.
Do not enable SMB1 (please note SMB1 is disabled by default in Samba from version 4.11.0 and onwards). This prevents the creation of symbolic links via SMB1. If SMB1 must be enabled for backwards compatibility then add the parameter:
unix extensions = no
to the [global] section of your smb.conf and restart smbd. This prevents SMB1 clients from creating symlinks on the exported file system.
However, if the same region of the file system is also exported using NFS, NFS clients can create symlinks that potentially can also hit the race condition. For non-patched versions of Samba we recommend only exporting areas of the file system by either SMB2 or NFS, not both.
1.2 Low
CVSS2
Attack Vector
LOCAL
Attack Complexity
HIGH
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
PARTIAL
Availability Impact
NONE
AV:L/AC:H/Au:N/C:N/I:P/A:N
2.5 Low
CVSS3
Attack Vector
LOCAL
Attack Complexity
HIGH
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
LOW
Availability Impact
NONE
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N
0.001 Low
EPSS
Percentile
44.9%