This week both SonicWall and Cisco have released patches for critical vulnerabilities in their networking products.

SonicWall zero day

The SonicWall vulnerability (CVE-2021-20016) is a zero-day under active attack – in fact it was used to breach SonicWall’s own network in January according to their security advisory.  The flaw affects SonicWall SMA 100 series devices and the company advises that users “must apply this patch IMMEDIATELY to avoid potential exploitation”.

The affected devices are:

• SonicWall Physical Appliances: SMA 200, SMA 210, SMA 400, SMA 410
• SonicWall Virtual Appliances: SMA 500v (Azure, AWS, ESXi, HyperV)

For customers not able to immediately apply the patch, SonicWall is offering to activate the Web Application Firewall module on the devices for free for 60 days in order to defend against the attack.  Details of how to activate the WAF are included in the security advisory.

If the vulnerability has been exploited the attackers could have gained access to the credentials for users of the device and so SonicWall advises that all passwords are reset and multi-factor authentication is enabled.

Cisco Small Business Routers patched

Cisco has released new firmware for several SMB routers that resolves multiple vulnerabilities in the web-based admin system that could allow unauthenticated remote attackers to execute arbitrary code on the device as the root user.

According to Cisco:

An attacker could exploit these vulnerabilities by sending a crafted HTTP request to the web-based management interface of an affected device. A successful exploit could allow the attacker to remotely execute arbitrary code on the device.

The vulnerability affects Cisco Small Business RV160, RV160W, RV260, RV260P, and RV260W VPN Routers.

Devices like these from Cisco and SonicWall often sit on the network perimeter and serve in the front line of defence from attacks coming from the Internet. Keeping infrastructure devices patched is essential in order to maintain a secure network perimeter.