On June 5, 2014, the OpenSSL Project issued a security advisory describing six exploits within OpenSSL code. Of the six vulnerabilities outlined by OpenSSL, A10 is only vulnerable to the MITM ChangeCipherSpec (CCS) Injection flaw (CVE-2014-0224). A10 Thunder or AX ADCs are vulnerable under specific conditions described below. The vulnerability can be immediately mitigated through server updates, and A10 will be issuing a patch to secure A10 ADC and TPS platforms. Timing and details for the patch follow.
Affected Platforms: Thunder and AX ADC series, Thunder TPS Series
Affected Software Versions: ACOS versions 2.6.1-GR1-x, 2.7.X, 3.0.0 (TPS)
The A10 Thunder and AX Application Delivery Controllers (ADC) are vulnerable to CVE-2014-0224- SSL/TLS Man-in-the-Middle attack. The vulnerability is limited to deployments where the Thunder or AX device is acting like an SSL client and is connecting to a back-end server that is running OpenSSL 1.0.1 or 1.0.2- beta1. For example, if a Thunder or AX ADC is terminating SSL traffic and re-encrypting the traffic before sending it to a back-end server—a server-side SSL deployment configured as “server-ssl” under the HTTPS virtual port for ADC solution — then the devices will be susceptible to the Man-in-the-Middle attack. In addition, if a Thunder or AX ADC is configured for SSL intercept as an SSL forward proxy using the “forwardproxy-enable” command, then it is also vulnerable.
Exposure on all Thunder and AX platforms is limited, as most SSL ADC deployments are configured for SSL offload and not for SSL re-encryption (server-side SSL).
With Thunder TPS, only the Web GUI is vulnerable to the MITM flaw.
There is limited vulnerability with EX and ID series products. We will be documenting vulnerabilities and mitigation recommendations shortly.
Thunder series SSL management interface (Web GUI) is not vulnerable.
Affected ADC Configurations (highlights denote specific configuration issues)
A10 Software defect 187969 has been filed to document the exploit.
ADC Server-side Deployment:
slb template server-ssl server-encryption
slb virtual-server vip 10.10.10.10
port 443 https
source-nat pool nat
template client-ssl client-encryption
template server-ssl server-encryption
Client side (client-ssl) SSL connections are not vulnerable to this exploit.
For SSL Intercept Deployment:
slb template client-ssl test
slb virtual-server vip1 0.0.0.0 acl 101
port 443 https
template client-ssl test
A10 products are NOT AFFECTED by these vulnerability advisories issued by OpenSSL on June 5, 2014:
- CVE-2014-0221, DTLS recursion flaw
- CVE-2014-0195, DTLS invalid fragment vulnerability
- CVE-2014-0198, SSL_MODE_RELEASE_BUFFERS NULL pointer dereference
- CVE-2010-5298, SSL_MODE_RELEASE_BUFFERS session injection or denial of service
- CVE-2014-3470, Anonymous ECDH denial of service