OpenTelemetry Core: Unbounded memory allocation in W3C Baggage propagation

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

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

EPSS

• CVE-2026-54285: 0.40% estimated exploitation activity in the next 30 days; percentile 34.52 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Overview 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. Impact The practical availability impact for most Node.js deployments is limited. Node.js enforces a default --max-http-header-size of 16,384 bytes on the total combined size of all HTTP headers, constraining what an external attacker can deliver before the propagator is reached. Additionally, the header is already in memory (parsed by the HTTP layer) by the time it reaches the propagator - the additional allocation is the overhead of splitting into entry objects, not an unbounded read. The risk is higher when transport-layer limits are absent - e.g., non-HTTP transports…

Published by the source

15 Jun 2026, 20:38 UTC

Last modified by the source

10 Sep 2026, 03:50 UTC

Source last checked

26 Oct 2026, 13:01 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-8988-4f7v-96qf

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-8988-4f7v-96qf

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# Patch Next advisory brief: CVE-2026-54285

Advisory: OpenTelemetry Core: Unbounded memory allocation in W3C Baggage propagation
IDs: CVE-2026-54285, GHSA-8988-4f7v-96qf
Record: https://patchnext.com/advisories/cve-2026-54285 (revision 2, source checked 26 Oct 2026, 13:01 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.3)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: @opentelemetry/core 2.8.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm @opentelemetry/core: affected < 2.8.0; fixed in 2.8.0

## Suggested inspection (read-only)
- `npm ls @opentelemetry/core --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on @opentelemetry/core.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-8988-4f7v-96qf (OSV record GHSA-8988-4f7v-96qf lists affected ranges: npm @opentelemetry/core >=0 <2.8.0 (fixed))
- Verified: https://github.com/advisories/GHSA-8988-4f7v-96qf (GitHub-reviewed advisory GHSA-8988-4f7v-96qf lists affected ranges: npm @opentelemetry/core >=0 <2.8.0)

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