Cisco NX-OS OpenSSL Multiple Vulnerabilities (cisco-sa-20150310-ssl) (FREAK)

medium Nessus Plugin ID 83528

Synopsis

The remote device is missing a vendor-supplied security patch.

Description

The remote Cisco device is running a version of NX-OS software that is affected by multiple vulnerabilities in its bundled OpenSSL library:

- A NULL pointer dereference flaw exists when the SSLv3 option isn't enabled and an SSLv3 ClientHello is received. This allows a remote attacker, using an unexpected handshake, to crash the daemon, resulting in a denial of service. (CVE-2014-3569)

- The BIGNUM squaring (BN_sqr) implementation does not properly calculate the square of a BIGNUM value. This allows remote attackers to defeat cryptographic protection mechanisms. (CVE-2014-3570)

- A NULL pointer dereference flaw exists with dtls1_get_record() when handling DTLS messages. A remote attacker, using a specially crafted DTLS message, can cause a denial of service. (CVE-2014-3571)

- A flaw exists with ECDH handshakes when using an ECDSA certificate without a ServerKeyExchange message. This allows a remote attacker to trigger a loss of forward secrecy from the ciphersuite. (CVE-2014-3572)

- A flaw exists when accepting non-DER variations of certificate signature algorithms and signature encodings due to a lack of enforcement of matches between signed and unsigned portions. A remote attacker, by including crafted data within a certificate's unsigned portion, can bypass fingerprint-based certificate-blacklist protection mechanisms. (CVE-2014-8275)

- A security feature bypass vulnerability, known as FREAK (Factoring attack on RSA-EXPORT Keys), exists due to the support of weak EXPORT_RSA cipher suites with keys less than or equal to 512 bits. A man-in-the-middle attacker may be able to downgrade the SSL/TLS connection to use EXPORT_RSA cipher suites which can be factored in a short amount of time, allowing the attacker to intercept and decrypt the traffic. (CVE-2015-0204)

- A flaw exists when accepting DH certificates for client authentication without the CertificateVerify message.
This allows a remote attacker to authenticate to the service without a private key. (CVE-2015-0205)

- A memory leak occurs in dtls1_buffer_record() when handling a saturation of DTLS records containing the same number sequence but for the next epoch. This allows a remote attacker to cause a denial of service.
(CVE-2015-0206)

Solution

Apply the patch or workaround supplied by the vendor.

See Also

http://www.nessus.org/u?bd646a4f

https://www.smacktls.com/#freak

Plugin Details

Severity: Medium

ID: 83528

File Name: cisco-sa-20150310-ssl-nxos.nasl

Version: 1.12

Type: combined

Family: CISCO

Published: 5/19/2015

Updated: 11/22/2019

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.2

CVSS v2

Risk Factor: Medium

Base Score: 5

Temporal Score: 3.7

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:N

CVSS Score Source: CVE-2015-0205

Vulnerability Information

CPE: cpe:/o:cisco:nx-os

Required KB Items: Host/Cisco/NX-OS/Version, Host/Cisco/NX-OS/Model, Host/Cisco/NX-OS/Device

Exploit Ease: No known exploits are available

Patch Publication Date: 3/10/2015

Vulnerability Publication Date: 10/16/2014

Reference Information

CVE: CVE-2014-3569, CVE-2014-3570, CVE-2014-3571, CVE-2014-3572, CVE-2014-8275, CVE-2015-0204, CVE-2015-0205, CVE-2015-0206

BID: 71934, 71935, 71936, 71937, 71939, 71940, 71941, 71942