MitM attack in Heimdal

1) Key management errors

EUVDB-ID: #VU29242

Risk: Low

CVSSv3.1: 4.2 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2019-12098

CWE-ID: CWE-320 - Key Management Errors

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a Man-in-the-Middle (MitM) attack.

The vulnerability exists due to Heimdal fails to verify anonymous PKINIT PA-PKINIT-KX key exchange within the krb5_init_creds_step() function in lib/krb5/init_creds_pw.c. A remote attacker can perform a MitM attack against the Heimdal client.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

heimdal: 7.0.1 - 7.5.0

External links

http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00002.html
http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00003.html
http://lists.opensuse.org/opensuse-security-announce/2019-08/msg00026.html
http://www.h5l.org/pipermail/heimdal-announce/2019-May/000009.html
http://github.com/heimdal/heimdal/commit/2f7f3d9960aa6ea21358bdf3687cee5149aa35cf
http://github.com/heimdal/heimdal/compare/3e58559...bbafe72
http://github.com/heimdal/heimdal/releases/tag/heimdal-7.6.0
http://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/GIXEDVVMPD6ZAJSMI2EZ7FNEIVNWE5PD/
http://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/SLXXIF4LOQEAEDAF4UGP2AO6WDNTDFUB/
http://seclists.org/bugtraq/2019/Jun/1
http://www.debian.org/security/2019/dsa-4455

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.