Answer in brief
CVE-2023-22491 records a High severity (CVSS 8.1) vulnerability in gatsby-transformer-remark has possible unsanitized JavaScript code injection. The current sources do not mark it as known exploited. The current feed maps gatsby-transformer-remark (npm), gatsby-transformer-remark (npm). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 8.1. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps gatsby-transformer-remark (npm), gatsby-transformer-remark (npm). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| gatsby-transformer-remarknpm | >=6.0.0 <6.3.2 | 6.3.2 |
| gatsby-transformer-remarknpm | >=0 <5.25.1 | 5.25.1 |
Published upstream
Jan 11, 2023
Evidence: source:osv:source_dates:source-dates:recordSource modified
Sep 10, 2026
Evidence: source:osv:source_dates:source-dates:recordFirst seen by HOL
Sep 10, 2026
### 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 `[email protected]` and `[email protected]` 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 [[email protected]](mailto:[email protected]).
Quoted source text, attributed separately from HOL analysis.