gatsby-transformer-remark vulnerable to unsanitized JavaScript code injection

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

Gatsby is a free and open source framework based on React that helps developers build websites and apps. 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. A patch has been introduced in `[email protected]` and `[email protected]` which mitigates the issue by disabling the `gray-matter` JavaScript Frontmatter engine. As a workaround, if an older version of `gatsby-transformer-remark` must be used, input passed into the plugin should be sanitized ahead of processing. It is encouraged for 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.

Source published

13 Jan 2023 18:05:00 UTC

Source modified

11 Mar 2025 13:34:01 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: cve-program · CVE Program Terms of Use. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · 8.1 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Gatsby is a free and open source framework based on React that helps developers build websites and apps. 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. A patch has been introduced in `[email protected]` and `[email protected]` which mitigates the issue by disabling the `gray-matter` JavaScript Frontmatter engine. As a workaround, if an older version of `gatsby-transformer-remark` must be used, input passed into the plugin should be sanitized ahead of processing. It is encouraged for 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.

Source published

Jan 13, 2023, 6:05:00 PM (timezone not stated)

Source modified

Mar 11, 2025, 1:34:01 PM (timezone not stated)

Observed here

12 Nov 2026 03:05:21 UTC

Source terms

ENISA EUVD · source terms and attribution apply

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: euvd · ENISA EUVD · source terms and attribution apply. Source text is retained; field grouping and change labels are provided by ChangeIntel.

EUVD CVSS 3.1 · 8.1 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Gatsby is a free and open source framework based on React that helps developers build websites and apps. 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. A patch has been introduced in `[email protected]` and `[email protected]` which mitigates the issue by disabling the `gray-matter` JavaScript Frontmatter engine. As a workaround, if an older version of `gatsby-transformer-remark` must be used, input passed into the plugin should be sanitized ahead of processing. It is encouraged for 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.

Source published

13 Jan 2023 19:15:12 UTC

Source modified

29 Sep 2026 15:06:00 UTC

Observed here

24 Oct 2026 21:17:28 UTC

Source terms

NIST NVD usage terms; underlying source attribution retained

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · [email protected] · Secondary · 8.1 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

CVSS 3.1 · [email protected] · Primary · 5.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

### 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]).

Source published

11 Jan 2023 18:27:15 UTC

Source modified

10 Sep 2026 03:49:51 UTC

Observed here

24 Oct 2026 13:17:17 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Publisher rating · HIGH