Vulnerability identifier: #VU34855

Vulnerability risk: High

CVSSv3.1: 8.5 [AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2015-5334

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
LibreSSL
Universal components / Libraries / Libraries used by multiple products

Vendor: OpenBSD

Description

The vulnerability allows remote attackers to perform a denial of service (DoS) attack.

The vulnerability exists due to insufficient validation of user-supplied input. A remote attacker can cause a denial of service (program crash) or possible execute arbitrary code via a crafted X.509 certificate, which triggers a stack-based buffer overflow.

Mitigation
Update to version 2.3.1.

Vulnerable software versions

LibreSSL: 2.3.0

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External links
http://ftp.openbsd.org/pub/OpenBSD/LibreSSL/libressl-2.3.1-relnotes.txt
http://lists.opensuse.org/opensuse-updates/2015-10/msg00050.html
http://packetstormsecurity.com/files/133998/Qualys-Security-Advisory-LibreSSL-Leak-Overflow.html
http://seclists.org/fulldisclosure/2015/Oct/75
http://www.securityfocus.com/archive/1/archive/1/536692/100/0/threaded

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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.