{"id":"CVE-2023-22491","aliases":["GHSA-7ch4-rr99-cqcw"],"url":"https://o3.security/vulnerability/CVE-2023-22491","summary":"gatsby-transformer-remark vulnerable to unsanitized JavaScript code injection ","details":"### Impact\nThe 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.\n\nTo 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:\n```\n---js\n((require(\"child_process\")).execSync(\"id >> /tmp/rce\"))\n--- \n```\n\n### Patches\nA 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.\n\n### Workarounds\nIf an older version of `gatsby-transformer-remark` 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\n### For more information\nEmail us at [security@gatsbyjs.com](mailto:security@gatsbyjs.com).","published":"2023-01-13T18:05:00.273Z","modified":"2026-08-12T03:51:36.041236045Z","cvss":{"score":8.1,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N"},"epss":{"score":0.00613,"percentile":0.47809,"asOf":"2026-09-17"},"cisaKev":null,"exploitsKnown":1,"affectedPackages":[{"ecosystem":"npm","name":"gatsby-transformer-remark","fixedVersion":"6.3.2"},{"ecosystem":"npm","name":"gatsby-transformer-remark","fixedVersion":"5.25.1"}],"fix":null,"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/22xxx/CVE-2023-22491.json"},{"type":"ADVISORY","url":"https://github.com/gatsbyjs/gatsby/security/advisories/GHSA-7ch4-rr99-cqcw"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-22491"},{"type":"PACKAGE","url":"https://github.com/gatsbyjs/gatsby"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:36.041236045Z"}}