#VU32312 Use-after-free in libebml - CVE-2015-8789

Vulnerability identifier: #VU32312

Vulnerability risk: High

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:Amber]

CVE-ID: CVE-2015-8789

CWE-ID: CWE-416

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
libebml
Other software / Other software solutions

Vendor: www.matroska.org

Description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a use-after-free error when processing a "deeply nested element with infinite size" followed by another element of an upper level in an EBML document. <a href="http://cwe.mitre.org/data/definitions/416. A context-dependent attackers can have unspecified impact.

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

Mitigation
Update to version 1.3.3.

Vulnerable software versions

libebml: 1.3.0

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External links
https://lists.matroska.org/pipermail/matroska-users/2015-October/006985.html
https://lists.opensuse.org/opensuse-updates/2016-01/msg00035.html
https://www.debian.org/security/2016/dsa-3538
https://www.securityfocus.com/bid/94924
https://www.talosintelligence.com/reports/TALOS-2016-0037/
https://github.com/Matroska-Org/libebml/blob/release-1.3.3/ChangeLog
https://github.com/Matroska-Org/libebml/commit/88409e2a94dd3b40ff81d08bf6d92f486d036b24

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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.