USN-3294-1: Bash vulnerabilities
Ubuntu Security Notice USN-3294-1
17th May, 2017
bash vulnerabilities
A security issue affects these releases of Ubuntu and its
derivatives:
- Ubuntu 17.04
- Ubuntu 16.10
- Ubuntu 16.04 LTS
- Ubuntu 14.04 LTS
Summary
Several security issues were fixed in Bash.
Software description
- bash
– GNU Bourne Again SHell
Details
Bernd Dietzel discovered that Bash incorrectly expanded the hostname when
displaying the prompt. If a remote attacker were able to modify a hostname,
this flaw could be exploited to execute arbitrary code. This issue only
affected Ubuntu 14.04 LTS, Ubuntu 16.04 LTS and Ubuntu 16.10.
(CVE-2016-0634)
It was discovered that Bash incorrectly handled the SHELLOPTS and PS4
environment variables. A local attacker could use this issue to execute
arbitrary code with root privileges. This issue only affected Ubuntu 14.04
LTS, Ubuntu 16.04 LTS and Ubuntu 16.10. (CVE-2016-7543)
It was discovered that Bash incorrectly handled the popd command. A remote
attacker could possibly use this issue to bypass restricted shells.
(CVE-2016-9401)
It was discovered that Bash incorrectly handled path autocompletion. A
local attacker could possibly use this issue to execute arbitrary code.
This issue only affected Ubuntu 17.04. (CVE-2017-5932)
Update instructions
The problem can be corrected by updating your system to the following
package version:
- Ubuntu 17.04:
-
bash
4.4-2ubuntu1.1
- Ubuntu 16.10:
-
bash
4.3-15ubuntu1.1
- Ubuntu 16.04 LTS:
-
bash
4.3-14ubuntu1.2
- Ubuntu 14.04 LTS:
-
bash
4.3-7ubuntu1.7
To update your system, please follow these instructions:
https://wiki.ubuntu.com/Security/Upgrades.
In general, a standard system update will make all the necessary changes.
References
Source: USN-3294-1: Bash vulnerabilities
