Amazon Linux 2 : runc (ALASDOCKER-2023-025)

high Nessus Plugin ID 176771

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 1.1.5-1. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2DOCKER-2023-025 advisory.

- runc is a CLI tool for spawning and running containers according to the OCI specification. In affected versions it was found that rootless runc makes `/sys/fs/cgroup` writable in following conditons: 1. when runc is executed inside the user namespace, and the `config.json` does not specify the cgroup namespace to be unshared (e.g.., `(docker|podman|nerdctl) run --cgroupns=host`, with Rootless Docker/Podman/nerdctl) or 2. when runc is executed outside the user namespace, and `/sys` is mounted with `rbind, ro` (e.g., `runc spec --rootless`; this condition is very rare). A container may gain the write access to user-owned cgroup hierarchy `/sys/fs/cgroup/user.slice/...` on the host . Other users's cgroup hierarchies are not affected.
Users are advised to upgrade to version 1.1.5. Users unable to upgrade may unshare the cgroup namespace (`(docker|podman|nerdctl) run --cgroupns=private)`. This is the default behavior of Docker/Podman/nerdctl on cgroup v2 hosts. or add `/sys/fs/cgroup` to `maskedPaths`. (CVE-2023-25809)

- runc through 1.1.4 has Incorrect Access Control leading to Escalation of Privileges, related to libcontainer/rootfs_linux.go. To exploit this, an attacker must be able to spawn two containers with custom volume-mount configurations, and be able to run custom images. NOTE: this issue exists because of a CVE-2019-19921 regression. (CVE-2023-27561)

- runc is a CLI tool for spawning and running containers according to the OCI specification. It was found that AppArmor can be bypassed when `/proc` inside the container is symlinked with a specific mount configuration. This issue has been fixed in runc version 1.1.5, by prohibiting symlinked `/proc`. See PR #3785 for details. users are advised to upgrade. Users unable to upgrade should avoid using an untrusted container image. (CVE-2023-28642)

Note that Nessus has not tested for these issues 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/ALASDOCKER-2023-025.html

https://alas.aws.amazon.com/cve/html/CVE-2023-25809.html

https://alas.aws.amazon.com/cve/html/CVE-2023-27561.html

https://alas.aws.amazon.com/cve/html/CVE-2023-28642.html

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

Plugin Details

Severity: High

ID: 176771

File Name: al2_ALASDOCKER-2023-025.nasl

Version: 1.2

Type: local

Agent: unix

Published: 6/6/2023

Updated: 9/15/2023

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

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5.3

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

CVSS Score Source: CVE-2023-28642

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 7

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

Temporal Vector: CVSS:3.0/E:P/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 Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 5/25/2023

Vulnerability Publication Date: 3/3/2023

Reference Information

CVE: CVE-2023-25809, CVE-2023-27561, CVE-2023-28642