A stack buffer overflow exists in radvdump before version 2.21 when parsing the Route Information Option of a crafted ICMPv6 Router Advertisement. The parser copies up to 2032 bytes into a 16‑byte in6_addr structure on the stack, overflowing it by up to 2016 bytes and enabling a remote attacker to execute arbitrary code on a host running radvdump. The deficit affects only radvdump; the radvd daemon remains vulnerable‑free.

The radvd dump utility from the radvd-project is affected when its version is older than 2.21. All builds of radvdump released before 2.21 are vulnerable, while releases starting at 2.21 incorporate the fix.

The CVSS score of 7.7 reflects significant severity. EPSS is not available and the vulnerability is not listed in the CISA KEV catalog, implying a currently unspecified exploitation likelihood. The most probable attack vector involves a crafted ICMPv6 Router Advertisement sent over the network to a host running radvdump, potentially yielding arbitrary code execution and full compromise of the targeted system.