GHSA-2933-Q333-QG83 i18next-fs-backend vulnerable to prototype pollution via crafted missing-key string

Impact i18next-fs-backend ≤ 2.6.5, when used to persist missing translation keys e.g. via i18next-http-middleware's missingKeyHandler exposed to untrusted input, is vulnerable to prototype pollution via crafted missing-key strings. Backend.writeFile splits each queued missing-key string on the...

i18next-http-middleware: MissingKeyHandler does not reject keys whose segments contain prototype-polluting names

Impact i18next-http-middleware ≤ 3.9.6's missingKeyHandler blocked the literal request-body keys proto, constructor, and prototype added in 3.9.3, see GHSA-5fgg-jcpf-8jjw, but did not reject dotted variants such as "proto.polluted". Downstream backends that split the missing-key string on a...

CVE-2026-48713

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...

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...