GHSA-xv83-x443-7rmw
HIGHHTML injection in search results via plaintext message highlighting
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.
Blast Radius
matrix-react-sdkReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects npm packages — download data is not available via public APIs for these ecosystems.
Description
Impact
Plain text messages containing HTML tags are rendered as HTML in the search results. To exploit this, an attacker needs to trick a user into searching for a specific message containing an HTML injection payload.
Cross-site scripting is possible by including resources from recaptcha.net and gstatic.com which are included in the default CSP.
Thanks to Cadence Ember for finding the injection and to S1m for finding possible XSS vectors.
Patches
Version 3.71.0 of the SDK fixes the issue.
Workarounds
Restarting the client will clear the injection.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | matrix-react-sdk | all versions | 3.71.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for matrix-react-sdk. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update matrix-react-sdk to 3.71.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-xv83-x443-7rmw 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 pinpoints whether GHSA-xv83-x443-7rmw is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-xv83-x443-7rmw. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-xv83-x443-7rmw in your dependencies?
O3 detects GHSA-xv83-x443-7rmw across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.