Red Hat update for krb5-appl

1) Buffer overflow

EUVDB-ID: #VU3031

Risk: Critical

CVSSv4.0: 9.3 [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 - 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

Install updates from vendor's website.

Vulnerable software versions

Red Hat Enterprise Linux for Scientific Computing: 6

Red Hat Enterprise Linux for IBM z Systems: 6

Red Hat Enterprise Linux Desktop: 6

Red Hat Enterprise Linux Workstation: 6

Red Hat Enterprise Linux Server: 6.0

CPE2.3

• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_scientific_computing:6:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_ibm_z_systems:6:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_desktop:6:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_workstation:6:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_server:6.0:*:*:*:*:red_hat_enterprise_linux:*:*

External links

https://access.redhat.com/errata/RHSA-2011:1852

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.