Dovecot up to 2.2.26 auth-policy Username input validation

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
4.7	$0-$5k	0.00

Summaryinfo

A vulnerability was found in Dovecot up to 2.2.26 and classified as problematic. Affected is an unknown function of the component auth-policy. Such manipulation of the argument Username as part of Unset leads to input validation. This vulnerability is uniquely identified as CVE-2016-8652. The attack can be launched remotely. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Dovecot up to 2.2.26 (Mail Server Software) and classified as problematic. Affected by this issue is an unknown code of the component auth-policy. The manipulation of the argument username as part of a Unset leads to a input validation vulnerability. Using CWE to declare the problem leads to CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. Impacted is availability. CVE summarizes:

The auth component in Dovecot before 2.2.27, when auth-policy is configured, allows a remote attackers to cause a denial of service (crash) by aborting authentication without setting a username.

The bug was discovered 02/16/2017. The weakness was disclosed 02/17/2017 by Aki Tuomi (Website). The advisory is shared for download at dovecot.org. This vulnerability is handled as CVE-2016-8652 since 10/12/2016. The attack may be launched remotely. No form of authentication is required for exploitation. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 96057 (Fedora 24 : 1:dovecot (2016-bb22a24d3d)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Fedora Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 276334 (Fedora Security Update for dovecot (FEDORA-2016-bb22a24d3d)).

Upgrading to version 2.2.27 eliminates this vulnerability. A possible mitigation has been published even before and not after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (96057) and SecurityFocus (BID 94639†). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Mail Server Software

Name

• Dovecot

Version

• 2.2.0
• 2.2.1
• 2.2.2
• 2.2.3
• 2.2.4
• 2.2.5
• 2.2.6
• 2.2.7
• 2.2.8
• 2.2.9
• 2.2.10
• 2.2.11
• 2.2.12
• 2.2.13
• 2.2.14
• 2.2.15
• 2.2.16
• 2.2.17
• 2.2.18
• 2.2.19
• 2.2.20
• 2.2.21
• 2.2.22
• 2.2.23
• 2.2.24
• 2.2.25
• 2.2.26

License

• open-source

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.8
VulDB Meta Temp Score: 4.7

VulDB Base Score: 3.7
VulDB Temp Score: 3.6
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.9
NVD Vector: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Input validation
CWE: CWE-20
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 96057
Nessus Name: Fedora 24 : 1:dovecot (2016-bb22a24d3d)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 65339
OpenVAS Name: Fedora Update for dovecot FEDORA-2016-bb22a24d3d
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Dovecot 2.2.27

Timelineinfo

10/12/2016 🔍
12/02/2016 +51 days 🔍
12/22/2016 +20 days 🔍
12/22/2016 +0 days 🔍
02/16/2017 +56 days 🔍
02/16/2017 +0 days 🔍
02/17/2017 +1 days 🔍
02/17/2017 +0 days 🔍
09/17/2024 +2769 days 🔍

Sourcesinfo

Advisory: dovecot.org
Researcher: Aki Tuomi
Status: Not defined

CVE: CVE-2016-8652 (🔍)
GCVE (CVE): GCVE-0-2016-8652
GCVE (VulDB): GCVE-100-97052
SecurityFocus: 94639 - Dovecot Auth Component CVE-2016-8652 Denial of Service Vulnerability
OSVDB: - CVE-2016-8652 - Dovecot - Denial of Service Issue

Entryinfo

Created: 02/17/2017 11:44
Updated: 09/17/2024 22:00
Changes: 02/17/2017 11:44 (75), 08/15/2020 12:28 (3), 09/17/2024 22:00 (19)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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