On Wednesday, Aug. 24, Cisco Systems has released some security patches for a critical flaw in Adaptive Security Appliance (ASA) firewalls found to be the target of an exploit cyberweapon linked to the U.S. National Security Agency (NSA). Security analysts expect that the networking company will soon release more fixes.
Cisco Firewalls Vulnerable To NSA's ExtraBacon Exploit
The security flaw in Cisco's ASA firewalls is exploited by a cyberweapon dubbed ExtraBacon. According to cybersecurity experts, this is one of the tools used by the Equation, a group believed to be a cyberespionage team linked to the NSA.
According to Computerworld, earlier this month the ExtraBacon exploit was released together with other exploits by a hacker group using the name Shadow Brokers. The group has put up online for auction files provided as a sample of a larger Equation set of hacking and cyberweapon tools.
A buffer overflow vulnerability is exploited by the ExtraBacon tool in the Simple Network Management Protocol (SNMP) implementation from Cisco's Adaptive Security Appliance software. According to TechTarget, after researches found an easy way to modify the SNMP exploit, the danger of the NSA-linked ExtraBacon exploit grew. The cyberweapon could be easily made to be effective against newer versions of Cisco's ASA software.
As long as they can send traffic to their SNMP interface on the affected devices, attackers can remotely execute rogue code. The only thing typically required in order to remotely execute rogue code on Cisco affected firewalls is being on the same internal network as the targeted devices.
As a measure against the NSA exploit cyberweapon, the networking company Cisco Systems updated its advisory in order to announce the availability of patched versions. The fixes come for different Cisco ASA branches, including 9.1.7(9), 9.5(3) and 9.6.1(11). According to the vendor, it is recommended to update devices using ASA software versions from the 8.x and 7.x branches to version 9.1.7(9).
The Cisco Firewall Services Module (FWSM), the Cisco Firepower Threat Defense (FTD) Software and Cisco PIX Firewalls are also affected by this vulnerability, in addition to ASA software. No patches will be provided for Cisco PIX Firewalls and Cisco Firewall Service Modules that have reached their end of life, but software version 6.0.1(2) was released for Cisco FTD.