OpenZFS up to 2.1.13/2.2.1 /etc/hosts.deny access control

Summaryinfo

A vulnerability classified as critical has been found in OpenZFS up to 2.1.13/2.2.1. Impacted is an unknown function of the file /etc/hosts.deny. The manipulation leads to access control. This vulnerability is traded as CVE-2023-49298. An attack has to be approached locally. There is no exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in OpenZFS up to 2.1.13/2.2.1 and classified as problematic. This issue affects some unknown processing of the file /etc/hosts.deny. The manipulation with an unknown input leads to a access control vulnerability. Using CWE to declare the problem leads to CWE-284. The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. Impacted is integrity, and availability. The summary by CVE is:

OpenZFS through 2.1.13 and 2.2.x through 2.2.1, in certain scenarios involving applications that try to rely on efficient copying of file data, can replace file contents with zero-valued bytes and thus potentially disable security mechanisms. NOTE: this issue is not always security related, but can be security related in realistic situations. A possible example is cp, from a recent GNU Core Utilities (coreutils) version, when attempting to preserve a rule set for denying unauthorized access. (One might use cp when configuring access control, such as with the /etc/hosts.deny file specified in the IBM Support reference.) NOTE: this issue occurs less often in version 2.2.1, and in versions before 2.1.4, because of the default configuration in those versions.

The weakness was shared 11/24/2023 as 15526. It is possible to read the advisory at web.archive.org. The identification of this vulnerability is CVE-2023-49298 since 11/24/2023. 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 233873 (Debian dla-4114 : libnvpair3linux - security update), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 2.1.4 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at Tenable (233873). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Name

• OpenZFS

Version

• 2.1.0
• 2.1.1
• 2.1.2
• 2.1.3
• 2.1.4
• 2.1.5
• 2.1.6
• 2.1.7
• 2.1.8
• 2.1.9
• 2.1.10
• 2.1.11
• 2.1.12
• 2.1.13
• 2.2.0
• 2.2.1

CPE 2.3info

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CPE 2.2info

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

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