Ubuntu update for GNU Libtasn1

1) Buffer overflow

EUVDB-ID: #VU6890

Risk: Medium

CVSSv4.0: 6.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2017-6891

CWE-ID: CWE-121 - Stack-based buffer overflow

Exploit availability: No

Description

A remote attacker can execute arbitrary code on the target system.

The vulnerability exists due to a boundary error in "asn1_find_node()" function (lib/parser_aux.c) within GnuTLS libtasn1 version 4.10 when processing a specially crafted assignments file via the e.g. asn1Coding utility. A remote attacker can trick the victim into opening a specially crafted file, trigger stack-based buffer overflow and execute arbitrary code with privileges of the current user.

Successful exploitation of the vulnerability may allow an attacker to compromise vulnerable system.

Mitigation

Ubuntu 17.04:

libtasn1-6 4.10-1ubuntu0.1

Ubuntu 16.10:

libtasn1-6 4.9-4ubuntu0.1

Ubuntu 16.04 LTS:

libtasn1-6 4.7-3ubuntu0.16.04.2

Ubuntu 14.04 LTS:

libtasn1-6 3.4-3ubuntu0.5

Vulnerable software versions

Ubuntu: 14.04 - 17.04

CPE2.3

• cpe:2.3:o:canonical:ubuntu:14.04:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu:16.04:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu:16.10:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu:17.04:*:*:*:*:*:*:*

External links

https://www.ubuntu.com/usn/usn-3309-1/

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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