Vulnerability identifier: #VU3031
Vulnerability risk: Critical
Exploitation vector: Network
Exploit availability: Yes
Vendor: FreeBSD Foundation
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The weakness exists due to buffer overflow in the encrypt_keyid() function of telnetd. A remote attacker can send a very large encryption key to telnetd daemon, trigger buffer overflow and execute arbitrary code with root privileges.
Successful exploitation of the vulnerability results in arbitrary code execution on the vulnerable system.
Note: the vulnerability was being actively exploited.
Update the latest version from vendor's website:
Vulnerable software versions
FreeBSD: 7.3 - 9.0
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability. However, a fully functional exploit for this vulnerability is available.