#VU820 Denial of service in OpenSSL - CVE-2016-6305

Vulnerability identifier: #VU820

Vulnerability risk: Low

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2016-6305

CWE-ID: CWE-120

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
OpenSSL
Server applications / Encryption software

Vendor: OpenSSL Software Foundation

Description
The vulnerability allows a remote unauthenticated user to cause DoS conditions on the vulnerable system.
The weakness is due to flaw in handling of SSL/TLS protocol during a call to SSL_peek(). By sending an empty record attackers can trigger the affected service hang or deny.
Successful exploitation of the vulnerability will result in denial of service on the vulnerable system.

Mitigation
Update 1.1.0 to version 1.1.0a.

Vulnerable software versions

OpenSSL: 1.1.0

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External links
https://www.openssl.org/news/secadv/20160922.txt
https://www.oracle.com/technetwork/security-advisory/cpuoct2016-2881722.html

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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.