{"id":"CVE-2025-27789","aliases":["GHSA-968p-4wvh-cqc8"],"url":"https://o3.security/vulnerability/CVE-2025-27789","summary":"Inefficient RexExp complexity in generated code with .replace when transpiling named capturing groups","details":"Babel is a compiler for writing next generation JavaScript. When using versions of Babel prior to 7.26.10 and 8.0.0-alpha.17 to compile regular expression named capturing groups, Babel will generate a polyfill for the `.replace` method that has quadratic complexity on some specific replacement pattern strings (i.e. the second argument passed to `.replace`). Generated code is vulnerable if all the following conditions are true: Using Babel to compile regular expression named capturing groups, using the `.replace` method on a regular expression that contains named capturing groups, and the code using untrusted strings as the second argument of `.replace`. This problem has been fixed in `@babel/helpers` and `@babel/runtime` 7.26.10 and 8.0.0-alpha.17. It's likely that individual users do not directly depend on `@babel/helpers`, and instead depend on `@babel/core` (which itself depends on `@babel/helpers`). Upgrading to `@babel/core` 7.26.10 is not required, but it guarantees use of a new enough `@babel/helpers` version. Note that just updating Babel dependencies is not enough; one will also need to re-compile the code. No known workarounds are available.","published":"2025-03-11T19:09:28.146Z","modified":"2026-07-15T01:49:02.344081290Z","cvss":{"score":6.2,"severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"@babel/helpers","fixedVersion":"7.26.10"},{"ecosystem":"npm","name":"@babel/runtime","fixedVersion":"7.26.10"},{"ecosystem":"npm","name":"@babel/runtime-corejs2","fixedVersion":"7.26.10"},{"ecosystem":"npm","name":"@babel/runtime-corejs3","fixedVersion":"7.26.10"},{"ecosystem":"npm","name":"@babel/helpers","fixedVersion":"8.0.0-alpha.17"},{"ecosystem":"npm","name":"@babel/runtime","fixedVersion":"8.0.0-alpha.17"},{"ecosystem":"npm","name":"@babel/runtime-corejs2","fixedVersion":"8.0.0-alpha.17"},{"ecosystem":"npm","name":"@babel/runtime-corejs3","fixedVersion":"8.0.0-alpha.17"}],"fix":{"url":"https://github.com/babel/babel/pull/17173","label":"babel/babel#17173"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/27xxx/CVE-2025-27789.json"},{"type":"ADVISORY","url":"https://github.com/babel/babel/security/advisories/GHSA-968p-4wvh-cqc8"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-27789"},{"type":"FIX","url":"https://github.com/babel/babel/pull/17173"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-07-15T01:49:02.344081290Z"}}