Cisco has warned customers that a vulnerability patched last year in its Adaptive Security Appliance (ASA) and Firepower Appliance products continues to be targeted by hackers.
The vulnerability, tracked as CVE-2018-0296, allows a remote, unauthenticated attacker to gain access to sensitive information through directory traversal techniques. It can also be exploited for denial-of-service (DoS) attacks.
The security hole was patched in early June 2018 and the first DoS attacks were spotted only a few weeks later. Several proof-of-concept (PoC) exploits have been made publicly available.
Cisco initially classified the vulnerability as high severity, but recently changed its rating to critical after learning of more attacks.
The networking giant updated its advisory in September 2019 to warn customers of new attack attempts, and Cisco Talos on Friday published a blog post to say that attacks “appeared to increase in frequency in the past several days and weeks.”
“This isn’t a new vulnerability, but as exploitation continues to increase, customers need to be aware of the risk of both a denial-of-service or unauthenticated information disclosure. Additionally, as we head into the holidays, people take time off, but adversaries do not,” Cisco Talos said.
When the first attacks exploiting CVE-2018-0296 were spotted, it was pointed out that it’s easy to find vulnerable Cisco devices on the web using Shodan and even Google.
Some experts also believe that CVE-2018-0296 may have been the DoS vulnerability whose exploitation caused interruptions to electrical system operations earlier this year at a power utility in the United States.
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