CVE-2026-48713

CVE-2026-48713 affects i18next-fs-backend prior to 2.6.6. The issue arises when crafted missing-key strings are persisted via missingKeyHandler, where Backend.writeFile() splits keys on keySeparator and the path walker could reach Object.prototype (e.g., a key like "proto .polluted"), allowing pr...

CVE-2026-48713 i18next-fs-backend: Prototype pollution via crafted missing-key string

Versions prior to 2.6.6 are vulnerable to prototype pollution via crafted missing-key strings when used to persist missing translation keys e.g. via i18next-http-middleware's missingKeyHandler exposed to untrusted input. Backend.writeFile splits each queued missing-key string on the configured...