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Unsanitized JavaScript code injection possible in gatsby-transformer-remark

High
mlgualtieri published GHSA-7ch4-rr99-cqcw Jan 11, 2023

Package

npm gatsby-transformer-remark (npm)

Affected versions

<=5.25.0; <=6.3.1

Patched versions

5.25.1; 6.3.2

Description

Impact

The gatsby-transformer-remark plugin prior to versions 5.25.1 and 6.3.2 passes input through to the gray-matter npm package, which is vulnerable to JavaScript injection in its default configuration, unless input is sanitized. The vulnerability is present in gatsby-transformer-remark when passing input in data mode (querying MarkdownRemark nodes via GraphQL). Injected JavaScript executes in the context of the build server.

To exploit this vulnerability untrusted/unsanitized input would need to be sourced by or added into a file processed by gatsby-transformer-remark. The following payload demonstrates a vulnerable configuration:

---js
((require("child_process")).execSync("id >> /tmp/rce"))
--- 

Patches

A patch has been introduced in gatsby-transformer-remark@5.25.1 and gatsby-transformer-remark@6.3.2 which mitigates the issue by disabling the gray-matter JavaScript Frontmatter engine. The patch introduces a new option, JSFrontmatterEngine which is set to false by default. When setting JSFrontmatterEngine to true, input passed to gatsby-plugin-mdx must be sanitized before processing to avoid a security risk. Warnings are displayed when enabling JSFrontmatterEngine to true or if it appears that the MarkdownRemark input is attempting to use the Frontmatter engine.

Workarounds

If an older version of gatsby-transformer-remark must be used, input passed into the plugin should be sanitized ahead of processing.

We encourage projects to upgrade to the latest major release branch for all Gatsby plugins to ensure the latest security updates and bug fixes are received in a timely manner.

For more information

Email us at security@gatsbyjs.com.

Severity

High

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

CVE ID

CVE-2023-22491

Weaknesses

No CWEs