Link following in Fedoraproject Fedora

1) Link following

EUVDB-ID: #VU40252

Risk: Low

CVSSv4.0: 5.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2016-3096

CWE-ID: CWE-59 - Improper Link Resolution Before File Access ('Link Following')

Exploit availability: No

Description

The vulnerability allows a local authenticated user to execute arbitrary code.

The create_script function in the lxc_container module in Ansible before 1.9.6-1 and 2.x before 2.0.2.0 allows local users to write to arbitrary files or gain privileges via a symlink attack on (1) /opt/.lxc-attach-script, (2) the archived container in the archive_path directory, or the (3) lxc-attach-script.log or (4) lxc-attach-script.err files in the temporary directory.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Fedora: 22 - 24

Ansible: 2.0 - 24

CPE2.3

• cpe:2.3:o:fedoraproject:fedora:22:*:*:*:*:*:*:*
• cpe:2.3:o:fedoraproject:fedora:23:*:*:*:*:*:*:*
• cpe:2.3:o:fedoraproject:fedora:24:*:*:*:*:*:*:*
• cpe:2.3:a:red_hat:ansible:2.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:red_hat:ansible:*:*:*:*:*:*:*:*

External links

https://lists.fedoraproject.org/pipermail/package-announce/2016-April/183103.html
https://lists.fedoraproject.org/pipermail/package-announce/2016-April/183132.html
https://lists.fedoraproject.org/pipermail/package-announce/2016-April/183252.html
https://lists.fedoraproject.org/pipermail/package-announce/2016-April/183274.html
https://lists.fedoraproject.org/pipermail/package-announce/2016-May/184175.html
https://bugzilla.redhat.com/show_bug.cgi?id=1322925
https://github.com/ansible/ansible/blob/v1.9.6-1/CHANGELOG.md#196-dancing-in-the-street---tbd
https://github.com/ansible/ansible/blob/v2.0.2.0-1/CHANGELOG.md#202-over-the-hills-and-far-away
https://github.com/ansible/ansible-modules-extras/pull/1941
https://github.com/ansible/ansible-modules-extras/pull/1941/commits/8c6fe646ee79f5e55361b885b7efed5bec72d4a4
https://groups.google.com/forum/#!topic/ansible-announce/E80HLZilTU0
https://groups.google.com/forum/#!topic/ansible-announce/tqiZbcWxYig
https://security.gentoo.org/glsa/201607-14

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.