SB2017071412 - Ubuntu update for Samba
Published: July 14, 2017 Updated: July 17, 2017
Security Bulletin ID
SB2017071412
Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Adjecent network
Highest impact
Information disclosure
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 security vulnerability.
1) Authentication bypass (CVE-ID: CVE-2017-11103)
The vulnerability allows a remote attacker to impersonate a trusted server and intercept users' credentials.The vulnerability exists due to the KDC-REP service name is stored in unencrypted "ticket" instead of encrypted "enc_part" and used later by the _krb5_extract_ticket() function. An attacker in local network can perform a man-in-the-middle attack, intercept the KDC-REP service name and impersonate a trusted server.
Successful exploitation of the vulnerability may allow an attacker to obtain credentials of all Samba users from Samba DRS replication service during password replication process between trusted and fake DC.
Remediation
Install update from vendor's website.