Cisco this week released its biannual Security Advisory Pack for IOS and IOS XE software, which fixes 10 security vulnerabilities, including six of “high severity.”
The top three are vulnerabilities that could be exploited by remote, unauthenticated attackers to cause a Denial of Service (DoS) condition.
The first of these bugs, tracked as CVE-2023-20080, affects the IPv6 DHCP version 6 (DHCPv6) relay and server functions of IOS and IOS XE software. Inadequate validation of data boundaries allows an attacker to send crafted DHCPv6 messages to an affected device and cause it to reload unexpectedly.
The second vulnerability, CVE-2023-20072, affects the fragmentation handling code of tunnel protocol packets and can be exploited by sending specially crafted fragmented packets to an affected system.
Cisco also addressed CVE-2023-20027, an issue in IOS and IOS XE software’s implementation of the IPv4 Virtual Fragmentation Reassembly (VFR) feature that exists because large packets are not properly reassembled when VFR is enabled is.
The vulnerability can be triggered by sending fragmented packets over a VFR-enabled interface on an affected device.
Another fatal DoS bug has been fixed in the HTTP-based client profiling feature of IOS XE software for wireless LAN controllers (WLCs). The issue tracked as CVE-2023-20067 can be exploited by a neighboring attacker without authentication.
“This vulnerability is due to insufficient input validation of the received traffic. An attacker could exploit this vulnerability by sending malicious traffic over a wireless access point. A successful exploit could allow the attacker to increase CPU utilization, which could lead to a DoS condition on an affected device and cause new wireless client associations to fail,” explains Cisco.
Cisco also addressed insufficient input validation in the IOS XE SD-WAN software CLI, which could allow an authenticated attacker to execute commands on the operating system with root-level privileges.
The bug, tracked as CVE-2023-20035, could allow a restricted attacker to take over a vulnerable system.
The sixth major flaw Cisco has addressed this week is CVE-2023-20065, an insufficient restrictions issue in the IOx application hosting subsystem of IOS XE software that could allow an authenticated attacker to escalate their privileges to root to expand.
Cisco’s biannual IOS and IOS XE software updates also include patches for medium-severity DoS, path traversal, and privilege escalation vulnerabilities.
This week, Cisco also released patches for three other critical bugs, including a secure boot issue in Catalyst 9300 series switches, a privilege escalation bug in DNA Center, and a DoS vulnerability in Access Point (AP) software.
Fixed several moderate issues in SD-WAN vManage software, DNA Center, Adaptive Security Appliance (ASA), Firepower Threat Defense (FTD), IOS and IOS XE software, and AP software.
Cisco says it is not aware of any of these vulnerabilities, which are exploited in malicious attacks. For more information on the resolved vulnerabilities, visit Cisco’s product security page.
See Also: Vulnerability Exposes Cisco Enterprise Routers to Disruptive Attacks
See also: Cisco Patches Critical Vulnerability in IP Phones
See also: Cisco patches high-severity vulnerabilities in ACI components