opentelemetry_sdk has 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-2026-48504: 0.42% estimated exploitation activity in the next 30 days; percentile 36.17 (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.

Summary BaggagePropagator::extractwithcontext in opentelemetrysdk did not enforce the W3C Baggage size limits before parsing an inbound baggage header. A large attacker-controlled header could cause unnecessary CPU work and short-lived heap allocations while parsing entries that would later be discarded by the SDK's baggage storage limits. The SDK now applies limits aligned with the W3C Baggage limits: - 64 list-members - 8192 bytes total Impact Services that accept untrusted inbound propagation headers may experience increased per-request resource usage when processing oversized baggage headers. This can contribute to denial-of-service risk, especially when application or transport-level header limits are absent or configured above the W3C Baggage limits. The impact is limited to availability. This issue does not expose telemetry data, modify telemetry data, or allow code execution. Patches Upgrade opentelemetrysdk to version 0.32.1 or later. Version 0.32.1 rejects baggage header…

Published by the source

25 Jun 2026, 18:40 UTC

Last modified by the source

25 Jun 2026, 18:40 UTC

Source last checked

26 Oct 2026, 15:42 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-w9wp-h8wv-79jx

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# Patch Next advisory brief: CVE-2026-48504

Advisory: opentelemetry_sdk has unbounded memory allocation in W3C Baggage propagation
IDs: CVE-2026-48504, GHSA-w9wp-h8wv-79jx
Record: https://patchnext.com/advisories/cve-2026-48504 (revision 1, source checked 26 Oct 2026, 15:42 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_sdk 0.32.1. A vendor fix does not mean a deployment is fixed.

## Affected components
- crates.io opentelemetry_sdk: affected <= 0.32.0; fixed in 0.32.1

## Suggested inspection (read-only)
- crates.io opentelemetry_sdk: check the installed version with your package manager.

## 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_sdk.
- 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://github.com/advisories/GHSA-w9wp-h8wv-79jx (GitHub-reviewed advisory GHSA-w9wp-h8wv-79jx lists affected ranges: crates.io opentelemetry_sdk >=0 <=0.32.0)

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