A vulnerability in the vDaemon process in Cisco IOS XE SD-WAN Software could allow an unauthenticated, remote attacker to cause a buffer overflow on an affected device. This vulnerability is due to insufficient bounds checking when an affected device processes traffic. An attacker could exploit this vulnerability by sending crafted traffic to the device. A successful exploit could allow the attacker to cause a buffer overflow and possibly execute arbitrary commands with root-level privileges, or cause the device to reload, which could result in a denial of service condition.
Use CWE-120, Cisco vendor hub and Ios Xe Sd-Wan product page to widen CVE-2021-34727 into its surrounding weakness, vendor, and product context.
Compare it with CVE-2025-20352, CVE-2021-1619 and CVE-2024-20455 for nearby disclosures in the same product family.