Heimdal up to 7.3 Kerberos 5 krb5_extract_ticket Impersonation data authenticity

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.3$0-$5k0.00

Summaryinfo

A vulnerability marked as critical has been reported in Heimdal up to 7.3. This vulnerability affects the function krb5_extract_ticket of the component Kerberos 5. This manipulation causes data authenticity (Impersonation). This vulnerability appears as CVE-2017-11103. The attack may be initiated remotely. There is no available exploit. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Heimdal up to 7.3 and classified as critical. Affected by this vulnerability is the function krb5_extract_ticket of the component Kerberos 5. The manipulation with an unknown input leads to a data authenticity vulnerability (Impersonation). The CWE definition for the vulnerability is CWE-345. The product does not sufficiently verify the origin or authenticity of data, in a way that causes it to accept invalid data. As an impact it is known to affect confidentiality, and integrity. The summary by CVE is:

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.

The bug was discovered 07/12/2017. The weakness was presented 07/13/2017 (Website). The advisory is shared at h5l.org. This vulnerability is known as CVE-2017-11103 since 07/07/2017. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available.

The vulnerability was handled as a non-public zero-day exploit for at least 1 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 101553 (Debian DLA-1027-1 : heimdal security update (Orpheus' Lyre)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Debian Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 185136 (HPE HP-UX running CIFS Server Multiple Vulnerabilities (HPESBUX03759)).

Upgrading to version 7.4 eliminates this vulnerability. A possible mitigation has been published 1 days after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (101553), SecurityFocus (BID 99551†) and SecurityTracker (ID 1038876†). See VDB-108405 and VDB-108954 for similar entries. Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.3

VulDB Base Score: 4.8
VulDB Temp Score: 4.6
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.1
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Name: Impersonation
Class: Data authenticity / Impersonation
CWE: CWE-345
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 101553
Nessus Name: Debian DLA-1027-1 : heimdal security update (Orpheus' Lyre)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 703909
OpenVAS Name: Debian Security Advisory DSA 3909-1 (samba - security update)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Upgrade: Heimdal 7.4

Timelineinfo

07/07/2017 🔍
07/12/2017 +5 days 🔍
07/12/2017 +0 days 🔍
07/12/2017 +0 days 🔍
07/13/2017 +1 days 🔍
07/13/2017 +0 days 🔍
07/14/2017 +1 days 🔍
07/14/2017 +0 days 🔍
07/17/2017 +3 days 🔍
12/12/2022 +1974 days 🔍

Sourcesinfo

Advisory: h5l.org
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-11103 (🔍)
GCVE (CVE): GCVE-0-2017-11103
GCVE (VulDB): GCVE-100-103513

OVAL: 🔍

SecurityFocus: 99551 - Heimdal CVE-2017-11103 Man in the Middle Security Bypass Vulnerability
SecurityTracker: 1038876

See also: 🔍

Entryinfo

Created: 07/14/2017 10:38
Updated: 12/12/2022 12:22
Changes: 07/14/2017 10:38 (83), 10/25/2019 16:55 (5), 12/12/2022 12:22 (4)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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