CVE-2017-11103

Name: CVE-2017-11103
Creator: NVD / NIST
Published: 2017-07-13T13:29:00.173+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.1/10EPSS 5.12%

Last modified Jun 17, 2026

CVE-2017-11103 is a high-severity vulnerability rated 8.1/10 on the CVSS scale. Heimdal before 7.4 allows remote attackers to impersonate services with Orpheus' Lyre attacks because it obtains service-principal names in a way that violates the Kerberos 5 protocol specification. In _krb5_extract_ticket() the KDC-REP service name must be obtained from the encrypted version stored in 'enc_part' instead of the unencrypted version stored in 'ticket'. EPSS estimates a 5.12% chance of exploitation in the next 30 days.

Description

Heimdal before 7.4 allows remote attackers to impersonate services with Orpheus' Lyre attacks because it obtains service-principal names in a way that violates the Kerberos 5 protocol specification. In _krb5_extract_ticket() the KDC-REP service name must be obtained from the encrypted version stored in 'enc_part' instead of the unencrypted version stored in 'ticket'. Use of the unencrypted version provides an opportunity for successful server impersonation and other attacks. NOTE: this CVE is only for Heimdal and other products that embed Heimdal code; it does not apply to other instances in which this part of the Kerberos 5 protocol specification is violated.

Metrics

CVSS 3.1

8.1/10

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

5.12%

91.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-345

Affected Software

Vendor	Product	Versions
Heimdal Project	Heimdal	< 7.4.0
Freebsd	Freebsd	All versions
Samba	Samba	>= 4.0.0, < 4.4.15
Samba	Samba	>= 4.5.0, < 4.5.12
Samba	Samba	>= 4.6.0, < 4.6.6
Apple	Iphone Os	< 11.0
Apple	Mac Os X	< 10.13.1
Debian	Debian Linux	8.0
Debian	Debian Linux	9.0
Debian	Debian Linux	10.0

References

http://www.debian.org/security/2017/dsa-3912Third Party Advisory
http://www.h5l.org/advisories.html?show=2017-07-11Broken Link
http://www.securityfocus.com/bid/99551Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1038876Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1039427Third Party Advisory, VDB Entry
https://github.com/heimdal/heimdal/releases/tag/heimdal-7.4.0Release Notes
https://support.apple.com/HT208112Third Party Advisory
https://support.apple.com/HT208144Third Party Advisory
https://support.apple.com/HT208221Third Party Advisory
https://www.freebsd.org/security/advisories/FreeBSD-SA-17:05.heimdal.ascThird Party Advisory
https://www.orpheus-lyre.info/Third Party Advisory
https://www.samba.org/samba/security/CVE-2017-11103.htmlThird Party Advisory
http://www.debian.org/security/2017/dsa-3912Third Party Advisory
http://www.h5l.org/advisories.html?show=2017-07-11Broken Link
http://www.securityfocus.com/bid/99551Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1038876Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1039427Third Party Advisory, VDB Entry
https://github.com/heimdal/heimdal/releases/tag/heimdal-7.4.0Release Notes
https://support.apple.com/HT208112Third Party Advisory
https://support.apple.com/HT208144Third Party Advisory
https://support.apple.com/HT208221Third Party Advisory
https://www.freebsd.org/security/advisories/FreeBSD-SA-17:05.heimdal.ascThird Party Advisory
https://www.orpheus-lyre.info/Third Party Advisory
https://www.samba.org/samba/security/CVE-2017-11103.htmlThird Party Advisory

Timeline

Published: Jul 13, 2017
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2017-11103?

How severe is CVE-2017-11103?

CVE-2017-11103 has a CVSS score of 8.1/10 (HIGH severity). The EPSS model estimates a 5.12% probability of exploitation in the next 30 days.

How do I fix CVE-2017-11103?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2017-11103?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST