SB2022013127 - Fedora 35 update for samba
Published: January 31, 2022
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 3 secuirty vulnerabilities.
1) Link following (CVE-ID: CVE-2021-44141)
The vulnerability allows a remote user to gain access to sensitive information.
The vulnerability exists due to insecure link following. A remote user with ability to write files to the exported part of the file system under a share via SMB1 unix extensions or via NFS can create a symlink to determine if a file or directory exists in an area of the server file system not exported under the share definition.
2) Out-of-bounds write (CVE-ID: CVE-2021-44142)
The vulnerability allows a remote attacker to compromise vulnerable system.
The vulnerability exists due to a boundary error when processing EA metadata while opening files in smbd within the VFS Samba module (vfs_fruit). A remote attacker with ability to write to file's extended attributes can trigger an out-of-bounds write and execute arbitrary code with root privileges.
Note, the vulnerability in vfs_fruit exists in the default configuration of the fruit VFS module using fruit:metadata=netatalk or fruit:resource=file.
3) Insufficient verification of data authenticity (CVE-ID: CVE-2022-0336)
The vulnerability allows a local user to impersonate arbitrary services.
The vulnerability exists due to Samba AD DC relies only on SPN (service principals name) to identify services on the network. An attacker with ability to modify SPNs can bypass implemented protection and cause a denial of service condition by adding an SPN that matches an existing service or impersonate services on the network.
Remediation
Install update from vendor's website.