CVE-2026-41692 is a medium-severity (CVSS 4.7) Cross-site Scripting (XSS) vulnerability in i18nextify. A fix is available for i18nextify — see the affected versions and patch details below.
i18nextify is vulnerable to DOM XSS via javascript:/data: URL schemes in translated href/src attributes
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-41692.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-41692 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,333 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
i18nextifynpmDescription
Summary
Versions of i18nextify prior to 4.0.8 substitute {{key}} interpolation tokens inside src and href attribute values with the raw string returned by i18next.t(). The substitution logic in src/localize.js (replaceInside handler around line 122) only guards against a duplicated http:// origin prefix — it does not validate the URL scheme of the substituted value. A translated value such as javascript:alert(1) or data:text/html,<script>...</script> is applied unchanged to the live DOM attribute.
Impact
When an attacker can influence the content of a translation file or the translation-backend response — compromised translation CDN, user-contributed locales, MITM on a plain-HTTP backend, write access to the translation JSON — they can:
- Set any
hrefon an anchor to ajavascript:URI, executing arbitrary JavaScript when the victim clicks the link. - Set any
srcon<iframe>,<object>, or<embed>to adata:text/htmlURI containing a full script payload that runs in the page's origin. - Use
vbscript:on legacy IE installations orfile:for local-resource navigation attacks.
This path is distinct from the general i18nextify design that intentionally renders HTML from translations — href/src schemes are narrow and attack-specific, and no legitimate translation needs javascript: or data:. The fix therefore blocks these schemes outright without changing other behaviour.
Also fixed in 4.0.8
debug/saveMissingURL-parameter substring match. The previous detectionwindow.location.search.indexOf('debug=true') > -1matched the substring anywhere in the query string. A URL like?nosaveMissing=truesilently enabledsaveMissingmode, causing the victim's browser to POST every unknown translation key to the configuredaddPath— a form of CSRF-style abuse of missing-key reporting.?track_debug=trueenabled verbose debug logging, leaking i18next internals to the console. Now usesURLSearchParamsfor exact parameter matching.- Optional
sanitize(html, ctx)hook. The library's core purpose is to render HTML from translations — a behaviour that is safe only when the translation source is fully trusted. Applications with partially-trusted sources (user-contributed locales, third-party CDN, MITM-exposed HTTP backend) can now wire a sanitizer (e.g. DOMPurify) viai18next.options.sanitize. Defaults to pass-through to preserve existing behaviour for the main use case.
Affected versions
All versions of i18nextify prior to 4.0.8.
Patch
Fixed in 4.0.8. The URL-scheme blocklist is ^\s*(javascript|data|vbscript|file)\s*: (case-insensitive) applied to each translated value before it is joined back into the href/src attribute. Values matching the blocklist are replaced with an empty string so the attribute becomes harmless rather than leaving the attacker's URL in place.
Workarounds
No workaround short of upgrading. If you cannot upgrade immediately, audit every translation file for javascript:, data:, vbscript:, and file: prefixes in any value that may reach an href/src position, and restrict translation-file write access to trusted operators. Serving translations over HTTPS and pinning the translation backend to an internal origin reduce the MITM surface.
Credits
Discovered via an internal security audit of the i18next ecosystem.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | i18nextify | all versions | 4.0.8npm install i18nextify@4.0.8 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for i18nextify, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update i18nextify to 4.0.8 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-41692 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-41692 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-41692. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-41692 in your dependencies?
O3 Security finds CVE-2026-41692 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.