#VU1975 Input validation error in OpenSSL - CVE-2016-2181

Vulnerability identifier: #VU1975

Vulnerability risk: Medium

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:Green]

CVE-ID: CVE-2016-2181

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
OpenSSL
Server applications / Encryption software

Vendor: OpenSSL Software Foundation

Description

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

The vulnerability exists due to insufficient validation of user-supplied input within the Anti-Replay feature in the DTLS implementation when using a new epoch number in conjunction with a large sequence number. A remote attacker can perform a denial of service (DoS) attack (false-positive packet drops) via spoofed DTLS records.

Mitigation
Install update from vendor's website.

Vulnerable software versions

OpenSSL: before 1.0.1u, 1.0.2i, 1.0.1u, 1.0.1u

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External links
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2016-2181
https://git.openssl.org/?p=openssl.git;a=commit;h=1fb9fdc3027b27d8eb6a1e6a846435b070980770

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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.