MIT Kerberos up to 1.12.x/1.13.1 kdcpreauth main.c access control

CVSS Meta Temp Score
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CTI Interest Score
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7.0$0-$5k0.00

A vulnerability was found in MIT Kerberos up to 1.12.x/1.13.1 (Network Authentication Software) and classified as critical. This issue affects an unknown function of the file plugins/preauth/otp/main.c of the component kdcpreauth. The manipulation with an unknown input leads to a access control vulnerability. Using CWE to declare the problem leads to CWE-264. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

The kdcpreauth modules in MIT Kerberos 5 (aka krb5) 1.12.x and 1.13.x before 1.13.2 do not properly track whether a client's request has been validated, which allows remote attackers to bypass an intended preauthentication requirement by providing (1) zero bytes of data or (2) an arbitrary realm name, related to plugins/preauth/otp/main.c and plugins/preauth/pkinit/pkinit_srv.c.

The weakness was released 05/25/2015 by Greg Hudson (Website). It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2015-2694 since 03/24/2015. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1068 according to MITRE ATT&CK.

The vulnerability scanner Nessus provides a plugin with the ID 83901 (FreeBSD : krb5 -- requires_preauth bypass in PKINIT-enabled KDC (406636fe-055d-11e5-aab1-d050996490d0)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family FreeBSD Local Security Checks. The commercial vulnerability scanner Qualys is able to test this issue with plugin 350078 (Amazon Linux Security Advisory for krb5: ALAS-2015-624).

Upgrading to version 1.13.2 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (83901), SecurityFocus (BID 74824†) and Vulnerability Center (SBV-50576†).

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
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CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.0

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
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Exploitinginfo

Class: Access control
CWE: CWE-264
CAPEC: 🔍
ATT&CK: 🔍

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 83901
Nessus Name: FreeBSD : krb5 -- requires_preauth bypass in PKINIT-enabled KDC (406636fe-055d-11e5-aab1-d050996490d0)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Port: 🔍

OpenVAS ID: 14611
OpenVAS Name: Amazon Linux Local Check: alas-2015-624
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
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Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Kerberos 1.13.2
Patch: github.com

Timelineinfo

03/24/2015 🔍
04/28/2015 +35 days 🔍
04/28/2015 +0 days 🔍
05/25/2015 +27 days 🔍
05/25/2015 +0 days 🔍
05/26/2015 +1 days 🔍
05/29/2015 +3 days 🔍
06/14/2015 +16 days 🔍
05/19/2022 +2531 days 🔍

Sourcesinfo

Vendor: mit.edu

Advisory: USN-2810-1
Researcher: Greg Hudson
Status: Not defined
Confirmation: 🔍

CVE: CVE-2015-2694 (🔍)
SecurityFocus: 74824 - MIT Kerberos 5 OTP and PKINIT kdcpreauth Modules Multiple Security Bypass Vulnerabilities
Vulnerability Center: 50576 - MIT Kerberos 5 Remote Security Bypass via PKINIT Enabled KDC, Medium

Entryinfo

Created: 05/26/2015 10:29 AM
Updated: 05/19/2022 10:34 AM
Changes: 05/26/2015 10:29 AM (60), 06/30/2017 06:06 AM (15), 05/19/2022 10:28 AM (4), 05/19/2022 10:34 AM (1)
Complete: 🔍
Cache ID: 18:ED3:40

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