Missing Initialization of a Variable in Cisco IOS and Cisco IOS XE - CVE-2021-34703
Published: September 24, 2021
Vulnerability identifier: #VU56864
CSH Severity: Low
CVSS v4: 6.9 [CVSS:4.0/AV:A/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2021-34703
CWE-ID: CWE-456
Exploitation vector: Adjecent network
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to improper initialization of a buffer in the Link Layer Discovery Protocol (LLDP) message parser. A remote authenticated attacker on the local network can trigger a reload of an affected device and cause a denial of service condition on the target system
Affected software
Cisco IOS
Cisco IOS XE
Cisco IOS XE
How to mitigate CVE-2021-34703
Install update from vendor's website.
Cisco IOS - addressed in versions 16.6.10, 16.9.8, 16.12.5, 16.12.5 b, 16.12.6
Cisco IOS XE - addressed in versions 16.6.10, 16.9.8, 16.12.5, 16.12.5 b, 16.12.6
Cisco IOS XE - addressed in versions 16.6.10, 16.9.8, 16.12.5, 16.12.5 b, 16.12.6