CVE-2023-48795

CVE-2023-48795 is a significant vulnerability discovered in the Siemens RUGGEDCOM APE1808, specifically in all versions with Palo Alto Networks Virtual NGFW configured to support the CHACHA20-POLY1305 algorithm or any Encrypt-then-MAC algorithms. This flaw, found within the SSH cryptographic network protocol, could potentially allow an attacker to downgrade the connection's security by truncating the extension negotiation message. The vulnerability was identified by academics from Ruhr-Universität Bochum and has been proven exploitable in Terrapin attacks. At the time of discovery, there was no immediate fix available for this vulnerability. This posed a considerable risk for users of the affected software, as it left them susceptible to potential security breaches. The vulnerability, which lies within the design and implementation of the software, has the potential to undermine the security integrity of the systems running the affected versions of the Siemens RUGGEDCOM APE1808. However, a temporary workaround has been proposed to mitigate the risk associated with CVE-2023-48795. Users can resolve this issue by adjusting the configuration of their in-use SSH profile to include at least one cipher and one MAC algorithm. This action effectively removes support for the vulnerable CHACHA20-POLY1305 and all Encrypt-then-MAC algorithms (those with -etm in the name) in the PAN-OS software. While this solution does not completely eliminate the vulnerability, it significantly reduces the risk until a permanent fix is made available.