CVE-2025-62517 is a medium-severity (CVSS 5.9) CWE-1321 vulnerability in rollbar. O3 Security confirms whether CVE-2025-62517 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Rollbar.js Prototype Pollution Vulnerability in merge()
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, a proxy for how much of the ecosystem is exposed.
rollbarnpmDescription
Rollbar.js offers error tracking and logging from Javascript to Rollbar. In versions before 2.26.5 and from 3.0.0-alpha1 to before 3.0.0-beta5, there is a prototype pollution vulnerability in merge(). If application code calls rollbar.configure() with untrusted input, prototype pollution is possible. This issue has been fixed in versions 2.26.5 and 3.0.0-beta5. A workaround involves ensuring that values passed to rollbar.configure() do not contain untrusted input.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | rollbar | all versions | 2.26.5 |
| 📦npm | rollbar | ≥ 3.0.0-alpha1&&< 3.0.0-beta5 | 3.0.0-beta5 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for rollbar. 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 rollbar to 2.26.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-62517 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-2025-62517 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-2025-62517. 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-2025-62517 in your dependencies?
O3 detects CVE-2025-62517 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.