Cisco has patched several high severity vulnerabilities, including ones that allow privilege escalation and denial-of-service (DoS) attacks, in its Unified Customer Voice Portal (CVP), Email Security, and NX-OS products.

Software updates released by the company for its Email Security product address a privilege escalation vulnerability (CVE-2018-0095) that allows a local attacker with guest user permissions to gain root access.

The flaw affects the administrative shell of the Email Security Appliance (ESA) and the Content Security Management Appliance (SMA), and it’s caused by an incorrect networking configuration.

“An attacker could exploit this vulnerability by authenticating to the targeted device and issuing a set of crafted, malicious commands at the administrative shell. An exploit could allow the attacker to gain root access on the device,” Cisco said.

A different high severity vulnerability (CVE-2018-0086) was patched by Cisco in its CVP product. The security hole allows a remote, unauthenticated attacker to cause a DoS condition on the device by sending specially crafted SIP invite traffic to the targeted appliance.

A high severity DoS bug (CVE-2018-0102) has also been patched in the NX-OS network operating system. An unauthenticated attacker with access to the network can leverage the flaw to cause vulnerable devices to reload.

“An attacker could exploit this vulnerability by sending a pong request to an affected device from a location on the network that causes the pong reply packet to egress both a FabricPath port and a non-FabricPath port. An exploit could allow the attacker to cause a dual or quad supervisor virtual port-channel (vPC) to reload,” Cisco said in its advisory.

Cisco has also informed customers of two other vulnerabilities affecting NX-OS, including a DoS and a user account deletion issue, but these have been classified as medium severity and they have yet to be patched.

All of these vulnerabilities have been discovered by Cisco itself and there is no evidence of exploitation for malicious purposes.

Cisco released more than 20 advisories on Wednesday, but a majority describe medium severity flaws for which the company has yet to release any patches.

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