Debian update for heimdal

1) Buffer overflow

EUVDB-ID: #VU3031

Risk: Critical

CVSSv3.1: 9.3 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H/E:F/RL:O/RC:C]

CVE-ID: CVE-2011-4862

CWE-ID: CWE-119 - Memory corruption

Exploit availability: Yes

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.

Mitigation

Update the affected package to version: 1.2.dfsg.1-2.1+lenny1, 1.4.0~git20100726.dfsg.1-2+squeeze1

Vulnerable software versions

Debian Linux: All versions

External links

http://www.freebsd.org/security/advisories/FreeBSD-SA-11:08.telnetd.asc

Q & A

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.