OpenTelemetry Rust: Unbounded memory allocation in W3C Baggage propagation

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No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

OpenTelemetry Rust is the Rust OpenTelemetry implementation. In 0.32.0 and earlier, BaggagePropagator::extract_with_context in opentelemetry_sdk did not enforce W3C Baggage size limits before parsing an inbound baggage header, so a large attacker-controlled header could cause unnecessary CPU work and short-lived heap allocations while parsing entries later discarded by the SDK's baggage storage limits. Services that accept untrusted inbound propagation headers may experience increased per-request resource usage when processing oversized baggage headers. This issue is fixed in version 0.32.1.

Source published

17 Jul 2026 20:13:45 UTC

Source modified

20 Jul 2026 15:18:22 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

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

OpenTelemetry Rust is the Rust OpenTelemetry implementation. In 0.32.0 and earlier, BaggagePropagator::extract_with_context in opentelemetry_sdk did not enforce W3C Baggage size limits before parsing an inbound baggage header, so a large attacker-controlled header could cause unnecessary CPU work and short-lived heap allocations while parsing entries later discarded by the SDK's baggage storage limits. Services that accept untrusted inbound propagation headers may experience increased per-request resource usage when processing oversized baggage headers. This issue is fixed in version 0.32.1.

Source published

17 Jul 2026 20:17:21 UTC

Source modified

24 Oct 2026 20:10:00 UTC

Observed here

25 Oct 2026 12:17:32 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 · 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

## Summary `BaggagePropagator::extract_with_context` in `opentelemetry_sdk` 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 `opentelemetry_sdk` to version `0.32.1` or later. Version `0.32.1` rejects `baggage` header values larger than 8192 bytes and limits extraction to the first 64 list-members. ## Workarounds If upgrading immediately is not possible, reject or limit inbound `baggage` headers larger than 8192 bytes before invoking OpenTelemetry propagation extraction. This can be enforced at a proxy, gateway, middleware layer, or custom carrier boundary. ## Resources - W3C Baggage limits: https://www.w3.org/TR/baggage/#limits - Related OpenTelemetry Java advisory: https://github.com/open-telemetry/opentelemetry-java/security/advisories/GHSA-rcgg-9c38-7xpx - Related OpenTelemetry Go advisory: https://github.com/open-telemetry/opentelemetry-go/security/advisories/GHSA-mh2q-q3fh-2475 - CVE-2026-48504 ## Credit tonghuaroot

Source published

25 Jun 2026 18:40:04 UTC

Source modified

10 Sep 2026 03:50:50 UTC

Observed here

24 Oct 2026 13:19:54 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:L

Publisher rating · MODERATE