CVE-2020-10696

VEX

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Last modified: UTC

Description

A path traversal flaw was found in Buildah. This flaw allows an attacker to trick a user into building a malicious container image hosted on an HTTP(s) server and then write files to the user's system anywhere that the user has permissions.

A path traversal flaw was found in Buildah. This flaw allows an attacker to trick a user into building a malicious container image hosted on an HTTP(s) server and then write files to the user's system anywhere that the user has permissions.

Statement

While OpenShift Container Platform does include the vulnerable buildah code, it doesn't make use of the vulnerable function. Podman is also included in OpenShift Container Platform, but it isn't used to perform a build, so it has been given a low impact rating. OpenShift Container Platform 3.11 now used podman from the RHEL Extra repository, and not the podman package shipped in the OpenShift 3.11 RPM repository. This issue is fixed in podman in RHEL Extras so we won't fix the podman package shipped in the OpenShift 3.11 RPM repository.

While OpenShift Container Platform does include the vulnerable buildah code, it doesn't make use of the vulnerable function. Podman is also included in OpenShift Container Platform, but it isn't used to perform a build, so it has been given a low impact rating.

OpenShift Container Platform 3.11 now used podman from the RHEL Extra repository, and not the podman package shipped in the OpenShift 3.11 RPM repository. This issue is fixed in podman in RHEL Extras so we won't fix the podman package shipped in the OpenShift 3.11 RPM repository.

Additional information

  • Bugzilla 1817651: buildah: Crafted input tar file may lead to local file overwrite during image build process
  • CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
  • FAQ: Frequently asked questions about CVE-2020-10696

Common Vulnerability Scoring System (CVSS) Score Details

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 HatNVD

CVSS v3 Base Score

8.8

8.8

Attack Vector

Network

Network

Attack Complexity

Low

Low

Privileges Required

None

None

User Interaction

Required

Required

Scope

Unchanged

Unchanged

Confidentiality Impact

High

High

Integrity Impact

High

High

Availability Impact

High

High

CVSS v3 Vector

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

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

Understanding the Weakness (CWE)

CWE-22

Integrity,Confidentiality,Availability

Technical Impact:Execute Unauthorized Code or Commands

The attacker may be able to create or overwrite critical files that are used to execute code, such as programs or libraries.

Integrity

Technical Impact:Modify Files or Directories

The attacker may be able to overwrite or create critical files, such as programs, libraries, or important data. If the targeted file is used for a security mechanism, then the attacker may be able to bypass that mechanism. For example, appending a new account at the end of a password file may allow an attacker to bypass authentication.

Confidentiality

Technical Impact:Read Files or Directories

The attacker may be able read the contents of unexpected files and expose sensitive data. If the targeted file is used for a security mechanism, then the attacker may be able to bypass that mechanism. For example, by reading a password file, the attacker could conduct brute force password guessing attacks in order to break into an account on the system.

Availability

Technical Impact:DoS: Crash, Exit, or Restart

The attacker may be able to overwrite, delete, or corrupt unexpected critical files such as programs, libraries, or important data. This may prevent the product from working at all and in the case of protection mechanisms such as authentication, it has the potential to lock out product users.

Acknowledgements

Red Hat would like to thank Erik Sjölund for reporting this issue.

Frequently Asked Questions

Why is Red Hat's CVSS v3 score or Impact different from other vendors?

My product is listed as "Under investigation" or "Affected", when will Red Hat release a fix for this vulnerability?

What can I do if my product is listed as "Will not fix"?

What can I do if my product is listed as "Fix deferred"?

What is a mitigation?

I have a Red Hat product but it is not in the above list, is it affected?

Why is my security scanner reporting my product as vulnerable to this vulnerability even though my product version is fixed or not affected?

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