Buffer overflow in FreeBSD - CVE-2011-4862
Published: December 28, 2016 / Updated: July 15, 2020
Vulnerability identifier: #VU3031
CSH Severity: Critical
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Red
CVE-ID: CVE-2011-4862
CWE-ID: CWE-119
Exploitation vector: Remote access
Exploit availability:
Public exploit is available
Vendor: FreeBSD Foundation
Affected software:
FreeBSD
FreeBSD
Detailed vulnerability description
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.
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.
How to mitigate CVE-2011-4862
Update the latest version from vendor's website:
http://security.FreeBSD.org/patches/SA-11:08/telnetd.patch
http://security.FreeBSD.org/patches/SA-11:08/telnetd.patch.asc
http://security.FreeBSD.org/patches/SA-11:08/telnetd.patch
http://security.FreeBSD.org/patches/SA-11:08/telnetd.patch.asc