{"id":"GHSA-mj46-r4gr-5x83","summary":"Unsanitized JavaScript code injection possible in gatsby-plugin-mdx","details":"### Impact\nThe gatsby-plugin-mdx plugin prior to versions 3.15.2 and 2.14.1 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 when passing input in both webpack (MDX files in `src/pages` or MDX file imported as component in frontend / React code) and data mode (querying MDX nodes via GraphQL).  Injected JavaScript executes in the context of the build server.\n\nTo exploit this vulnerability untrusted/unsanitized input would need to be sourced or added into an MDX file.  The following MDX payload demonstrates a vulnerable configuration:\n```\n---js\n((require(\"child_process\")).execSync(\"id \u003e\u003e /tmp/rce\"))\n--- \n```\n\n### Patches\nA patch has been introduced in `gatsby-plugin-mdx@3.15.2` and `gatsby-plugin-mdx@2.14.1` 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 MDX input is attempting to use the Frontmatter engine.\n\n### Workarounds\nIf an older version of `gatsby-plugin-mdx` must be used, input passed into the plugin should be sanitized ahead of processing.\n\n**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.**\n\n### Credits\nWe would like to thank Snyk [snyk.io] for initially bringing the issue to our attention, as well as Feng Xiao and Zhongfu Su, who reported the issue to Snyk.\n\n### For more information\nEmail us at [security@gatsbyjs.com](mailto:security@gatsbyjs.com).\n","aliases":["CVE-2022-25863","SNYK-JS-GATSBYPLUGINMDX-2405699"],"modified":"2026-07-08T06:50:01.480369243Z","published":"2022-06-03T22:32:06Z","database_specific":{"nvd_published_at":"2022-06-10T20:15:00Z","cwe_ids":["CWE-502"],"severity":"HIGH","github_reviewed":true,"github_reviewed_at":"2022-06-03T22:32:06Z"},"references":[{"type":"WEB","url":"https://github.com/gatsbyjs/gatsby/security/advisories/GHSA-mj46-r4gr-5x83"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2022-25863"},{"type":"WEB","url":"https://github.com/gatsbyjs/gatsby/pull/35830"},{"type":"WEB","url":"https://github.com/gatsbyjs/gatsby/pull/35830/commits/f214eb0694c61e348b2751cecd1aace2046bc46e"},{"type":"WEB","url":"https://drive.google.com/file/d/1EoCzbwTWOM8-fjvwMbH3bqcZ2iKksxTW/view?usp=sharing"},{"type":"PACKAGE","url":"https://github.com/gatsbyjs/gatsby"},{"type":"WEB","url":"https://snyk.io/vuln/SNYK-JS-GATSBYPLUGINMDX-2405699"}],"affected":[{"package":{"name":"gatsby-plugin-mdx","ecosystem":"npm","purl":"pkg:npm/gatsby-plugin-mdx"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"2.14.1"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2022/06/GHSA-mj46-r4gr-5x83/GHSA-mj46-r4gr-5x83.json"}},{"package":{"name":"gatsby-plugin-mdx","ecosystem":"npm","purl":"pkg:npm/gatsby-plugin-mdx"},"ranges":[{"type":"SEMVER","events":[{"introduced":"3.0.0"},{"fixed":"3.15.2"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2022/06/GHSA-mj46-r4gr-5x83/GHSA-mj46-r4gr-5x83.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N"}]}