CVE-2026-0969
HIGHCVE-2026-0969 is a high-severity (CVSS 8.8) Code Injection vulnerability in next-mdx-remote. O3 Security confirms whether CVE-2026-0969 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Arbitrary code execution in React server-side rendering of untrusted MDX content
Blast Radius
Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.
next-mdx-remotenpmDescription
The serialize function used to compile MDX in next-mdx-remote is vulnerable to arbitrary code execution due to insufficient sanitization of MDX content. This vulnerability, CVE-2026-0969, is fixed in next-mdx-remote 6.0.0.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | next-mdx-remote | ≥ 4.3.0&&< 6.0.0 | 6.0.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for next-mdx-remote. 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 next-mdx-remote to 6.0.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-0969 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 CVE-2026-0969 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 CVE-2026-0969. 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-2026-0969 in your dependencies?
O3 detects CVE-2026-0969 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.