CVE-2026-54285
MEDIUMCVE-2026-54285 is a medium-severity (CVSS 5.3) CWE-770 vulnerability in @opentelemetry/core. O3 Security confirms whether CVE-2026-54285 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
opentelemetry-js: Unbounded memory allocation in W3C Baggage propagation
Blast Radius
Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.
@opentelemetry/corenpmDescription
opentelemetry-js is the OpenTelemetry JavaScript Client. Prior to 2.8.0, W3CBaggagePropagator.extract() in @opentelemetry/core does not enforce size limits when parsing inbound baggage HTTP headers. The W3C Baggage specification recommends a maximum of 8,192 bytes and 180 entries; these limits were only enforced on the outbound (inject()) path, not on the inbound (extract()) path. Parsing oversized baggage causes memory allocation proportional to the header size without any cap. This vulnerability is fixed in 2.8.0.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | @opentelemetry/core | all versions | 2.8.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @opentelemetry/core. 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 @opentelemetry/core to 2.8.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-54285 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-2026-54285 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-2026-54285. 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-2026-54285 in your dependencies?
O3 detects CVE-2026-54285 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.