# CVE-2026-115730: i18next-http-backend: Namespace value starting with / forms a protocol-relative URL when loadPath/addPath places {{ns}} right after a / (bypass of the // check added for GHSA-xvq9-wjp8-hwqf)

Source: https://junglewise.ai/threats/cve-2026-115730-i18next-http-backend-4-0-2-contains-an-incomplete-fix-in  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-23  
License: CC BY 4.0 with a link back

CVE-2026-115730 · Severity: low · CVSS 3.1 · Published 2026-10-23

i18next-http-backend 4.0.2 contains an incomplete fix in interpolateUrl() that allows attackers to redirect translation requests by supplying an ns value starting with a slash. Attackers controlling the namespace value can form a protocol-relative URL in loadPath or addPath templates to load attacker-hosted translations, enabling UI content injection and cross-site scripting.

Technologies: [i18next-http-backend (npm)](https://junglewise.ai/threats/technologies/i18next-http-backend). Vendors: [npm](https://junglewise.ai/threats/vendors/npm).

## Quick answers

**Is CVE-2026-115730 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-115730 being exploited in the wild.

**How severe is CVE-2026-115730?** Low severity, with a CVSS score of 3.1, published 23 October 2026.

**Which products and versions are affected?** i18next-http-backend (npm) < 4.0.3, SEMVER:introduced=0,fixed=4.0.3.

**Is there a fix for CVE-2026-115730?** Yes. i18next-http-backend (npm): upgrade to 4.0.3 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2026-115730?** Check whether you run i18next-http-backend (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- i18next-http-backend (npm): upgrade to 4.0.3 or later

  ```sh
  npm install i18next-http-backend@4.0.3
  ```


## Affected products

- i18next-http-backend (npm) < 4.0.3, SEMVER:introduced=0,fixed=4.0.3

## Identifiers

- CVE-2026-115730
- GHSA-9jhj-wvmw-cfx5

## Related threats

- [i18next-http-backend: Query-parameter injection through & and = in lng when loadPath/addPath puts {{lng}} in the query string](https://junglewise.ai/threats/cve-2026-118258-i18next-http-backend-is-a-backend-layer-for-i18next-that-loads)
- [Duplicate Advisory: Namespace value starting with / forms a protocol-relative URL when loadPath/addPath places {{ns}} right after a / (bypass of the // check added for GHSA-xvq9-wjp8-hwqf)](https://junglewise.ai/threats/duplicate-advisory-namespace-value-starting-with-forms-a-protocol-0773444c)
- [i18next-http-backend incomplete URL validation permits SSRF](https://junglewise.ai/threats/cve-2026-105800-i18next-http-backend-is-a-backend-layer-for-i18next-that-loads)
- [i18next-http-backend URL injection and path traversal](https://junglewise.ai/threats/cve-2026-41691-i18next-http-backend-url-injection-and-path-traversal)