CVE-2023-27561

Description

A flaw was found in runc. An attacker who controls the container image for two containers that share a volume can race volume mounts during container initialization by adding a symlink to the rootfs that points to a directory on the volume.

Statement

The vulnerability in runc, related to Incorrect Access Control in libcontainer/rootfs_linux.go, is classified as a moderate severity issue due to its prerequisites for exploitation and the level of access required by an attacker. To exploit this vulnerability, an attacker must have the capability to spawn two containers with custom volume-mount configurations and execute custom images within these containers. This restricts the attack vector to scenarios where an attacker already has a certain level of access to the container environment. Additionally, the vulnerability leads to an escalation of privileges, potentially allowing an attacker to gain elevated permissions on the host system. While the impact of privilege escalation is significant, the specific conditions required for successful exploitation mitigate the overall severity to moderate.

This CVE exists because of a CVE-2019-19921 regression.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score777
Attack VectorLocalLocalLocal
Attack ComplexityHighHighHigh
Privileges RequiredLowLowLow
User InteractionNoneNoneNone
ScopeUnchangedUnchangedUnchanged
ConfidentialityHighHighHigh
Integrity ImpactHighHighHigh
Availability ImpactHighHighHigh

Vector

Red Hat: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

NVD: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

cve.org: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Understanding the Weakness (CWE)

Confidentiality,Integrity,Access Control

Technical Impact: Read Files or Directories; Modify Files or Directories; Bypass Protection Mechanism

An attacker may be able to traverse the file system to unintended locations and read or overwrite the contents of unexpected files. If the files are used for a security mechanism than an attacker may be able to bypass the mechanism.

Frequently Asked Questions

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