Linux Kernel up to 5.3.2 AF_APPLETALK Network net/appletalk/ddp.c atalk_create default permission

Summaryinfo

A vulnerability has been found in Linux Kernel up to 5.3.2 and classified as critical. This impacts the function atalk_create of the file net/appletalk/ddp.c of the component AF_APPLETALK Network Module. This manipulation causes default permission. The identification of this vulnerability is CVE-2019-17054. The attack can only be executed locally. There is no exploit available. Applying a patch is the recommended action to fix this issue.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 5.3.2 (Operating System) and classified as critical. Affected by this vulnerability is the function atalk_create of the file net/appletalk/ddp.c of the component AF_APPLETALK Network Module. The manipulation with an unknown input leads to a default permission vulnerability. The CWE definition for the vulnerability is CWE-276. During installation, installed file permissions are set to allow anyone to modify those files. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

atalk_create in net/appletalk/ddp.c in the AF_APPLETALK network module in the Linux kernel through 5.3.2 does not enforce CAP_NET_RAW, which means that unprivileged users can create a raw socket, aka CID-6cc03e8aa36c.

The weakness was shared 10/01/2019 by Ori Nimron as confirmed git commit (GIT Repository). The advisory is shared at git.kernel.org. The vendor cooperated in the coordination of the public release. This vulnerability is known as CVE-2019-17054 since 10/01/2019. An attack has to be approached locally. A single authentication is necessary for exploitation. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1222 for this issue. The advisory points out:

Ori Nimron pointed out that there are a number of places in the kernel where you can create a raw socket, without having to have the CAP_NET_RAW permission.

The vulnerability scanner Nessus provides a plugin with the ID 246891 (Linux Distros Unpatched Vulnerability : CVE-2019-17054), which helps to determine the existence of the flaw in a target environment.

Applying a patch is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The vulnerability will be addressed with the following lines of code:

rc = -EPERM;
if (sock->type == SOCK_RAW && !kern && !capable(CAP_NET_RAW))
   goto out;

To resolve this, here's a short patch series to test these odd and old protocols for this permission before allowing the creation to succeed

The vulnerability is also documented in the vulnerability database at Tenable (246891). The entries VDB-142787, VDB-142788, VDB-142790 and VDB-142791 are related to this item. If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.3.0
• 5.3.1
• 5.3.2

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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