Amazon Linux 2 : runc (ALASECS-2024-044)

low Nessus Plugin ID 209063

Synopsis

The remote Amazon Linux 2 host is missing a security update.

Description

The version of runc installed on the remote host is prior to 1.1.14-1. It is, therefore, affected by a vulnerability as referenced in the ALAS2ECS-2024-044 advisory.

runc is a CLI tool for spawning and running containers according to the OCI specification. runc 1.1.13 and earlier, as well as 1.2.0-rc2 and earlier, can be tricked into creating empty files or directories in arbitrary locations in the host filesystem by sharing a volume between two containers and exploiting a race with `os.MkdirAll`. While this could be used to create empty files, existing files would not be truncated. An attacker must have the ability to start containers using some kind of custom volume configuration. Containers using user namespaces are still affected, but the scope of places an attacker can create inodes can be significantly reduced. Sufficiently strict LSM policies (SELinux/Apparmor) can also in principle block this attack -- we suspect the industry standard SELinux policy may restrict this attack's scope but the exact scope of protection hasn't been analysed. This is exploitable using runc directly as well as through Docker and Kubernetes. The issue is fixed in runc v1.1.14 and v1.2.0-rc3.

Some workarounds are available. Using user namespaces restricts this attack fairly significantly such that the attacker can only create inodes in directories that the remapped root user/group has write access to.
Unless the root user is remapped to an actualuser on the host (such as with rootless containers that don't use `/etc/sub[ug]id`), this in practice means that an attacker would only be able to create inodes in world-writable directories. A strict enough SELinux or AppArmor policy could in principle also restrict the scope if a specific label is applied to the runc runtime, though neither the extent to which the standard existing policies block this attack nor what exact policies are needed to sufficiently restrict this attack have been thoroughly tested. (CVE-2024-45310)

Tenable has extracted the preceding description block directly from the tested product security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Run 'yum update runc' to update your system.

See Also

https://alas.aws.amazon.com/AL2/ALASECS-2024-044.html

https://alas.aws.amazon.com/cve/html/CVE-2024-45310.html

https://alas.aws.amazon.com/faqs.html

Plugin Details

Severity: Low

ID: 209063

File Name: al2_ALASECS-2024-044.nasl

Version: 1.2

Type: local

Agent: unix

Published: 10/15/2024

Updated: 12/11/2024

Supported Sensors: Agentless Assessment, Continuous Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Low

Score: 2.4

CVSS v2

Risk Factor: Low

Base Score: 2.1

Temporal Score: 1.6

Vector: CVSS2#AV:L/AC:L/Au:N/C:N/I:P/A:N

CVSS Score Source: CVE-2024-45310

CVSS v3

Risk Factor: Low

Base Score: 3.6

Temporal Score: 3.2

Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:amazon:linux:runc, cpe:/o:amazon:linux:2, p-cpe:/a:amazon:linux:runc-debuginfo

Required KB Items: Host/local_checks_enabled, Host/AmazonLinux/release, Host/AmazonLinux/rpm-list

Exploit Ease: No known exploits are available

Patch Publication Date: 10/10/2024

Vulnerability Publication Date: 9/3/2024

Reference Information

CVE: CVE-2024-45310