The Authentication Proxy feature in Cisco IOS does not properly handle invalid AAA return codes from RADIUS and TACACS+ servers, which allows remote attackers to bypass authentication in opportunistic circumstances via a connection attempt that triggers an invalid code, as demonstrated by a connection attempt with a blank password, aka Bug IDs CSCuo09400 and CSCun16016.
| Product | Vulnerable range | Fixed version | Advisory |
|---|---|---|---|
| n/a n/a | — | not specified | advisory ↗ |