OpenTelemetry JavaScript: Denial of service in `JaegerPropagator` via unhandled exception on a malformed header

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OpenTelemetry JavaScript is the OpenTelemetry JavaScript client. Prior to 2.9.0, @opentelemetry/propagator-jaeger decodes incoming uber-trace-id and uberctx-* HTTP header values with decodeURIComponent() without handling decode errors, allowing an unauthenticated remote attacker to send a malformed percent-encoded value that throws an uncaught URIError and terminates a Node.js process using JaegerPropagator as the active propagator. This issue is fixed in version 2.9.0.

Source published

8 Jul 2026 16:03:58 UTC

Source modified

8 Jul 2026 19:41:27 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: cve-program · CVE Program Terms of Use. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

OpenTelemetry JavaScript is the OpenTelemetry JavaScript client. Prior to 2.9.0, @opentelemetry/propagator-jaeger decodes incoming uber-trace-id and uberctx-* HTTP header values with decodeURIComponent() without handling decode errors, allowing an unauthenticated remote attacker to send a malformed percent-encoded value that throws an uncaught URIError and terminates a Node.js process using JaegerPropagator as the active propagator. This issue is fixed in version 2.9.0.

Source published

Jul 8, 2026, 4:03:58 PM (timezone not stated)

Source modified

Jul 8, 2026, 7:41:27 PM (timezone not stated)

Observed here

7 Nov 2026 13:26:03 UTC

Source terms

ENISA EUVD · source terms and attribution apply

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: euvd · ENISA EUVD · source terms and attribution apply. Source text is retained; field grouping and change labels are provided by ChangeIntel.

EUVD CVSS 3.1 · 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

OpenTelemetry JavaScript is the OpenTelemetry JavaScript client. Prior to 2.9.0, @opentelemetry/propagator-jaeger decodes incoming uber-trace-id and uberctx-* HTTP header values with decodeURIComponent() without handling decode errors, allowing an unauthenticated remote attacker to send a malformed percent-encoded value that throws an uncaught URIError and terminates a Node.js process using JaegerPropagator as the active propagator. This issue is fixed in version 2.9.0.

Source published

8 Jul 2026 17:17:27 UTC

Source modified

25 Oct 2026 17:10:00 UTC

Observed here

27 Oct 2026 15:15:33 UTC

Source terms

NIST NVD usage terms; underlying source attribution retained

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · [email protected] · Secondary · 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

## Summary `@opentelemetry/propagator-jaeger` decodes incoming HTTP header values with `decodeURIComponent()` without handling decode errors. A single request carrying a malformed percent-encoded value (for example a bare `%`) in an `uber-trace-id` or `uberctx-*` header throws an uncaught `URIError`, terminating any Node.js process that uses `JaegerPropagator` as its active propagator. ## Impact **Denial of Service:** Any unauthenticated remote attacker who can send an HTTP request to a service that has `JaegerPropagator` registered as the global propagator (e.g. via `OTEL_PROPAGATORS=jaeger` or `propagation.setGlobalPropagator(new JaegerPropagator())`) can terminate the process with a single request. Confidentiality and integrity are not affected. ## Am I affected? This issue affects only a specific, opt-in configuration. If you use OpenTelemetry's default propagators (W3C TraceContext and Baggage), you are **not** affected. You are affected only if you have registered `JaegerPropagator` as the active propagator. Check for: - `@opentelemetry/propagator-jaeger` in your dependency tree, **and** - `OTEL_PROPAGATORS` set to `jaeger` (Jaeger only), **or** a direct `propagation.setGlobalPropagator(new JaegerPropagator())` call in your code. Note: if `JaegerPropagator` is combined with other propagators through a `CompositePropagator` (for example `OTEL_PROPAGATORS=jaeger,tracecontext`), the process does not terminate - the composite propagator catches the error - but affected requests silently fail to extract context. You should still upgrade. ## Patched versions - `@opentelemetry/propagator-jaeger` 2.9.0 ## Remediation Update `@opentelemetry/propagator-jaeger` to 2.9.0 or later. The propagator now ignores header values it cannot decode instead of throwing. **Interim mitigation (if you cannot update):** Trace-context headers should never be accepted unfiltered from untrusted callers. Until you can upgrade, strip or validate the `uber-trace-id` and `uberctx-*` headers on inbound requests at your edge - for example with a reverse proxy, API gateway, or load balancer (nginx, Envoy, etc.) - so that only trusted upstream services can set them. ## Details `JaegerPropagator.extract()` calls `decodeURIComponent()` on raw header values at two unguarded call sites: the `uber-trace-id` trace header and each `uberctx-*` baggage value. `decodeURIComponent()` throws `URIError: URI malformed` on invalid percent-encoding. Because the HTTP instrumentation extracts context before its request-handler error wrapper, and a single configured propagator is not wrapped in a `CompositePropagator` (which would otherwise catch the error), the exception propagates as an `uncaughtException` and terminates the process. ## Proof of concept Against a service using `JaegerPropagator`: ```bash curl -H 'uberctx-user: %' http://target/ # or curl -H 'uber-trace-id: %' http://target/ ``` The Node.js process exits with `URIError: URI malformed` and subsequent requests are refused.

Source published

21 Jul 2026 19:07:28 UTC

Source modified

10 Sep 2026 03:50:51 UTC

Observed here

24 Oct 2026 13:17:17 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Publisher rating · HIGH