CVE-2026-39882
mediumpriority · track · 0EPSS 0.002 · 9 %ileDEEUFRRUUSEPSS · scored 2026-10-27
OpenTelemetry-Go is the Go implementation of OpenTelemetry. Prior to 1.43.0, the otlp HTTP exporters (traces/metrics/logs) read the full HTTP response body into an in-memory bytes.Buffer without a size cap. This is exploitable for memory exhaustion when the configured collector endpoint is attacker-controlled (or a network attacker can mitm the exporter connection). This vulnerability is fixed in 1.43.0.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (26)
Products and version ranges known to be affected.
- Red Hat Enterprise Linux Multicluster Engine for Kubernetesall versionscert_bundDEcpe:/o:redhat:enterprise_linux:multicluster_engine_for_kubernetes
- Red Hat OpenShift Container Platform 4.22.5all versionscert_bundDEcpe:/a:redhat:openshift:container_platform_4.22.5
advisories (4)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-2334Red Hat OpenShift Container Platform (fast-uri,OpenTelemetry-Go) : Mehrere SchwachstellenDeutsch2026-07-14csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Red Hat OpenShift Container Platform ausnutzen, um Sicherheitsvorkehrungen zu umgehen oder einen Denial-of-Service-Zustand auszulösen.
- GHSA-w8rr-5gcm-pp58opentelemetry-go: OTLP HTTP exporters read unbounded HTTP response bodies2026-04-08ghsa · osvUS
overview: this report shows that the otlp HTTP exporters (traces/metrics/logs) read the full HTTP response body into an in-memory `bytes.Buffer` without a size cap. this is exploitable for memory exhaustion when the configured collector endpoint is attacker-controlled (or a network attacker can mitm the exporter connection). severity HIGH not claiming: this is a remote dos against every default deployment. claiming: if the exporter sends traces to an untrusted collector endpoint (or over a network segment where mitm is realistic), that endpoint can crash the process via a large response body. callsite (pinned): - exporters/otlp/otlptrace/otlptracehttp/client.go:199 - exporters/otlp/otlptrace/otlptracehttp/client.go:230 - exporters/otlp/otlpmetric/otlpmetrichttp/client.go:170 - exporters/otlp/otlpmetric/otlpmetrichttp/client.go:201 - exporters/otlp/otlplog/otlploghttp/client.go:190 - exporters/otlp/otlplog/otlploghttp/client.go:221 permalinks (pinned): - https://github.com/open-telemetry/opentelemetry-go/blob/248da958375e4dfb4a1105645107be3ef04b1c59/exporters/otlp/otlptrace/otlptracehttp/client.go#L199 - https://github.com/open-telemetry/opentelemetry-go/blob/248da958375e4dfb4a1105645107be3ef04b1c59/exporters/otlp/otlptrace/otlptracehttp/client.go#L230 - https://github.com/open-telemetry/opentelemetry-go/blob/248da958375e4dfb4a1105645107be3ef04b1c59/exporters/otlp/otlpmetric/otlpmetrichttp/client.go#L170 - https://github.com/open-telemetry/opentelemetry-go/blob/248da958375e4dfb4a1105645107be3ef04b1c59/exporters/otlp/otlpmetric/otlpmetrichttp/client.go#L201 - https://github.com/open-telemetry/opentelemetry-go/blob/248da958375e4dfb4a1105645107be3ef04b1c59/exporters/otlp/otlplog/otlploghttp/client.go#L190 - https://github.com/open-telemetry/opentelemetry-go/blob/248da958375e4dfb4a1105645107be3ef04b1c59/exporters/otlp/otlplog/otlploghttp/client.go#L221 root cause: each exporter client reads `resp.Body` using `io.Copy(&respData, resp.Body)` into a `bytes.Buffer` on both success and error paths, with no upper bound. impact: a malicious collector can force large transient heap allocations during export (peak memory scales with attacker-chosen response size) and can potentially crash the instrumented process (oom). affected component: - go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp - go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp - go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp repro (local-only): ```bash unzip poc.zip -d poc cd poc make canonical resp_bytes=33554432 chunk_delay_ms=0 ``` expected output contains: ``` [CALLSITE_HIT]: otlptracehttp.UploadTraces::io.Copy(resp.Body) [PROOF_MARKER]: resp_bytes=33554432 peak_alloc_bytes=118050512 ``` control (same env, patched target): ```bash unzip poc.zip -d poc cd poc make control resp_bytes=33554432 chunk_delay_ms=0 ``` expected control output contains: ``` [CALLSITE_HIT]: otlptracehttp.UploadTraces::io.Copy(resp.Body) [NC_MARKER]: resp_bytes=33554432 peak_alloc_bytes=512232 ``` attachments: poc.zip (attached) [PR_DESCRIPTION.md](https://github.com/user-attachments/files/25564272/PR_DESCRIPTION.md) [attack_scenario.md](https://github.com/user-attachments/files/25564273/attack_scenario.md) [poc.zip](https://github.com/user-attachments/files/25564271/poc.zip) Fixed in: https://github.com/open-telemetry/opentelemetry-go/pull/8108
- CERTFR-2026-AVI-1385Multiples vulnérabilités dans les produits VMwareFrançais2026-10-26vendor · certfrFR
- GO-2026-4985Oversized OTLP HTTP response bodies can cause memory exhaustion in go.opentelemetry.io/otel/exporters/otlp2026-05-26vendor · osvUS
The OTLP HTTP exporters (traces, metrics, and logs) do not limit the size of the HTTP response body read from the collector. A malicious or misconfigured collector can send a large response body, leading to excessive memory consumption and potential process termination (OOM).
also known as (6)
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sources
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references (8)
External citations — patches, advisories, analysis.
- http://github.com/open-telemetry/opentelemetry-go/releases/Patchcnnvd
- https://access.redhat.com/security/cve/cve-2026-39882cnnvd
- https://github.com/open-telemetry/opentelemetry-go/pull/8108cnnvd
- https://github.com/open-telemetry/opentelemetry-go/security/advisories/GHSA-w8rr-5gcm-pp58cnnvd
- https://github.com/open-telemetry/opentelemetry-go/pull/8108enisa_euvd
- https://github.com/open-telemetry/opentelemetry-go/security/advisories/GHSA-w8rr-5gcm-pp58enisa_euvd
- https://github.com/open-telemetry/opentelemetry-go/pull/8108Patchnvd
- https://github.com/open-telemetry/opentelemetry-go/security/advisories/GHSA-w8rr-5gcm-pp58Third Party Advisorynvd
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