libuser up to 0.56.13-7/0.60-6 Blacklist Filter /etc/passwd chfn GECOS input validation

CVSS Meta Temp Score
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CTI Interest Score
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3.0$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, has been found in libuser up to 0.56.13-7/0.60-6. This vulnerability affects the function chfn of the file /etc/passwd of the component Blacklist Filter. Performing a manipulation of the argument GECOS results in input validation. This vulnerability is cataloged as CVE-2015-3245. Furthermore, there is an exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in libuser up to 0.56.13-7/0.60-6. This affects the function chfn of the file /etc/passwd of the component Blacklist Filter. The manipulation of the argument GECOS with an unknown input leads to a input validation vulnerability. CWE is classifying the issue as 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. This is going to have an impact on availability. The summary by CVE is:

Incomplete blacklist vulnerability in the chfn function in libuser before 0.56.13-8 and 0.60 before 0.60-7, as used in the userhelper program in the usermode package, allows local users to cause a denial of service (/etc/passwd corruption) via a newline character in the GECOS field.

The weakness was shared 08/11/2015 with Qualys (Website). It is possible to read the advisory at qualys.com. This vulnerability is uniquely identified as CVE-2015-3245 since 04/10/2015. Attacking locally is a requirement. The successful exploitation needs a authentication. Technical details and a public exploit are known.

A public exploit has been developed by Qualys Corporation and been published before and not just after the advisory. The exploit is shared for download at exploit-db.com. It is declared as proof-of-concept. The vulnerability was handled as a non-public zero-day exploit for at least 15 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 84964 (Amazon Linux AMI : usermode / libuser (ALAS-2015-572)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Amazon Linux Local Security Checks. The commercial vulnerability scanner Qualys is able to test this issue with plugin 350546 (Amazon Linux Security Advisory for libuser: AL2012-2015-085).

Upgrading to version 0.56.13-8 or 0.60-7 eliminates this vulnerability.

The vulnerability is also documented in the databases at Exploit-DB (37706), Tenable (84964) and SecurityFocus (BID 76021†). The entry VDB-76960 is related to this item. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 3.3
VulDB Meta Temp Score: 3.0

VulDB Base Score: 3.3
VulDB Temp Score: 3.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

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

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Author: Qualys Corporation
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 84964
Nessus Name: Amazon Linux AMI : usermode / libuser (ALAS-2015-572)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍

OpenVAS ID: 14611
OpenVAS Name: Amazon Linux Local Check: ALAS-2015-572
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Exploit-DB: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: libuser 0.56.13-8/0.60-7

Timelineinfo

04/10/2015 🔍
07/23/2015 +104 days 🔍
07/27/2015 +4 days 🔍
07/27/2015 +0 days 🔍
08/11/2015 +15 days 🔍
08/11/2015 +0 days 🔍
08/12/2015 +1 days 🔍
06/25/2024 +3240 days 🔍

Sourcesinfo

Advisory: RHSA-2015:1482
Organization: Qualys
Status: Not defined
Confirmation: 🔍

CVE: CVE-2015-3245 (🔍)
GCVE (CVE): GCVE-0-2015-3245
GCVE (VulDB): GCVE-100-76959
SecurityFocus: 76021 - libuser CVE-2015-3245 Local Denial of Service Vulnerability
SecurityTracker: 1033040

scip Labs: https://www.scip.ch/en/?labs.20161013
See also: 🔍

Entryinfo

Created: 08/12/2015 10:22
Updated: 06/25/2024 06:10
Changes: 08/12/2015 10:22 (58), 10/03/2017 12:10 (17), 06/07/2022 14:18 (4), 06/07/2022 14:22 (1), 06/25/2024 06:10 (15)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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