CVE-2016-2126
Published: 19 December 2016
Samba version 4.0.0 up to 4.5.2 is vulnerable to privilege elevation due to incorrect handling of the PAC (Privilege Attribute Certificate) checksum. A remote, authenticated, attacker can cause the winbindd process to crash using a legitimate Kerberos ticket. A local service with access to the winbindd privileged pipe can cause winbindd to cache elevated access permissions.
From the Ubuntu Security Team
Volker Lendecke discovered that Kerberos PAC validation implementation in Samba contained multiple vulnerabilities. An authenticated attacker could use this to cause a denial of service or gain administrative privileges.
Notes
| Author | Note |
|---|---|
| mdeslaur | 4.0.0+ |
Priority
Status
| Package | Release | Status |
|---|---|---|
|
samba Launchpad, Ubuntu, Debian |
precise |
Not vulnerable
|
| trusty |
Released
(2:4.3.11+dfsg-0ubuntu0.14.04.4)
|
|
| upstream |
Needs triage
|
|
| xenial |
Released
(2:4.3.11+dfsg-0ubuntu0.16.04.3)
|
|
| yakkety |
Released
(2:4.4.5+dfsg-2ubuntu5.2)
|
|
| zesty |
Released
(2:4.4.5+dfsg-2ubuntu7)
|
|
|
samba4 Launchpad, Ubuntu, Debian |
precise |
Ignored
(end of life)
|
| trusty |
Does not exist
|
|
| upstream |
Needs triage
|
|
| xenial |
Does not exist
|
|
| yakkety |
Does not exist
|
|
| zesty |
Does not exist
|
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 6.5 |
| Attack vector | Network |
| Attack complexity | Low |
| Privileges required | Low |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | None |
| Integrity impact | None |
| Availability impact | High |
| Vector | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |