Linux Kernel 3.2.x/3.4.x/3.5.x avahi/NetworkManager af_netlink.c scm_send SCM_CREDENTIALS improper authentication

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7.5$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in Linux Kernel 3.2.x/3.4.x/3.5.x. This affects the function scm_send of the file af_netlink.c of the component avahi/NetworkManager. Such manipulation of the argument SCM_CREDENTIALS leads to improper authentication. This vulnerability is listed as CVE-2012-3520. There is no available exploit. Applying a patch is advised to resolve this issue.

Detailsinfo

A vulnerability was found in Linux Kernel 3.2.x/3.4.x/3.5.x (Operating System) and classified as critical. Affected by this issue is the function scm_send of the file af_netlink.c of the component avahi/NetworkManager. The manipulation of the argument SCM_CREDENTIALS with an unknown input leads to a improper authentication vulnerability. Using CWE to declare the problem leads to CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. Impacted is confidentiality, integrity, and availability. CVE summarizes:

The Netlink implementation in the Linux kernel before 3.2.30 does not properly handle messages that lack SCM_CREDENTIALS data, which might allow local users to spoof Netlink communication via a crafted message, as demonstrated by a message to (1) Avahi or (2) NetworkManager.

The weakness was presented 08/21/2012 by Pablo Neira Ayuso as e0e3cea46d31 as confirmed git commit (GIT Repository). The advisory is shared for download at git.kernel.org. The public release was coordinated in cooperation with the vendor. This vulnerability is handled as CVE-2012-3520 since 06/14/2012. The attack needs to be approached locally. A simple authentication is required for exploitation. There are known technical details, but no exploit is available. This bug was introduced in commit 16e572626961 (af_unix: dont send SCM_CREDENTIALS by default).

The vulnerability scanner Nessus provides a plugin with the ID 69612 (Amazon Linux AMI : kernel (ALAS-2012-122)), 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 165318 (SUSE Security Update for Kernel: Security and Bug Fix Update (openSUSE-SU-2012:1330-1)).

Applying the patch e0e3cea46d31 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. A possible mitigation has been published immediately after the disclosure of the vulnerability. This patch forces passing credentials for netlink, as before the regression. Another fix would be to not add SCM_CREDENTIALS in netlink messages if not provided by the sender, but it might break some programs.

The vulnerability is also documented in the databases at Tenable (69612), SecurityFocus (BID 55152†), OSVDB (84837†), Secunia (SA50323†) and SecurityTracker (ID 1027434†). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.8
VulDB Meta Temp Score: 7.5

VulDB Base Score: 7.8
VulDB Temp Score: 7.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Improper authentication
CWE: CWE-287
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 69612
Nessus Name: Amazon Linux AMI : kernel (ALAS-2012-122)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Port: 🔍

OpenVAS ID: 864646
OpenVAS Name: Fedora Update for kernel FEDORA-2012-12490
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
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Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

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

Patch: e0e3cea46d31
McAfee IPS: 🔍
McAfee IPS Version: 🔍

Timelineinfo

06/14/2012 🔍
08/21/2012 +68 days 🔍
08/21/2012 +0 days 🔍
08/21/2012 +0 days 🔍
08/21/2012 +0 days 🔍
08/21/2012 +0 days 🔍
08/22/2012 +1 days 🔍
08/22/2012 +0 days 🔍
08/23/2012 +1 days 🔍
08/23/2012 +0 days 🔍
08/27/2012 +4 days 🔍
10/03/2012 +37 days 🔍
09/04/2013 +336 days 🔍
03/27/2021 +2761 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: e0e3cea46d31
Researcher: Pablo Neira Ayuso
Status: Confirmed
Confirmation: 🔍
Coordinated: 🔍

CVE: CVE-2012-3520 (🔍)
GCVE (CVE): GCVE-0-2012-3520
GCVE (VulDB): GCVE-100-6008

OVAL: 🔍

SecurityFocus: 55152 - Linux Kernel Netlink Message Handling Local Privilege Escalation Vulnerability
Secunia: 50323 - Linux Kernel Netlink Message Handling Privilege Escalation Vulnerability, Less Critical
OSVDB: 84837
SecurityTracker: 1027434 - Linux Kernel Netlink SCM_CREDENTIALS Processing Flaw Lets Local Users Gain Elevated Privileges
Vulnerability Center: 35965 - Linux Kernel 2.6.39-rc6 and Earlier and 3.0 Through 3.3.5 Local Privileges Escalation Vulnerability, High

Entryinfo

Created: 08/27/2012 10:32
Updated: 03/27/2021 13:51
Changes: 08/27/2012 10:32 (85), 04/16/2017 10:43 (14), 03/27/2021 13:51 (3)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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