CVE-2026-115730

i18next-http-backend 4.0.2 Protocol-Relative URL Injection via Namespace in interpolateUrl

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.

Affected

i18next · i18next-http-backend

CVSS v4.0 VULNCHECK

2.3 LOWCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CVSS v3.1 VULNCHECK

3.1 LOWCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N

EPSS

0.32% chance of exploitation in the next 30 days, 25th percentile

Published

2026-10-23

Updated

2026-10-29

Proof-of-concept exploits (1)

• advisories/GHSA-9jhj-wvmw-cfx5find archive

CVE references

• i18next/i18next-http-backend/commit/042c3d4e4e9d73b2ae3aa76b22cb45d48f1e35b7PATCH
• i18next/i18next-http-backend/security/advisories/GHSA-9jhj-wvmw-cfx5VENDOR
• i18next/i18next-http-backend/security/advisories/GHSA-xvq9-wjp8-hwqfVENDOR
• https://www.vulncheck.com/advisories/i18next-http-backend-4.0.2-protocol-relative-url-inj…ADVISORY

References

• CVE Record
• NVD entry