Vulnerability in go.opentelemetry.io/otel/sdk/log (CVE-2026-81872)
Summary
Vulnerability in go.opentelemetry.io/otel/sdk/log (CVE-2026-81872). Risk of unauthorized operations or information disclosure. Exploitable via BatchingProcessor. Mitigation: upgrade to 0.21.0 or later.
Original description
The description as published by the source.
Summary
A BatchingProcessor in go.opentelemetry.io/otel/sdk/log can enter a tight CPU loop when the asynchronous export buffer is full. Under exporter backpressure, attacker-driven high-volume log emission can keep the queue at or above the batch size, causing repeated immediate export retries and a denial of service through CPU exhaustion.
Introduced in commit: 4af9c20
Details
NewBatchingProcessor wraps the exporter with newBufferExporter(exporter, 1) (sdk/log/batch.go:116-122), so the asynchronous export input can fill quickly when the downstream exporter blocks. The poll goroutine dequeues a batch with b.q.TryDequeue, calls b.exporter.EnqueueExport(r), and then immediately sends on b.pollTrigger whenever qLen >= b.batchSize (sdk/log/batch.go:129-165).
bufferExporter.EnqueueExport is non-blocking: it sends to e.input if possible and returns false in the default case when the channel is full (sdk/log/exporter.go:221-248). TryDequeue leaves q.len unchanged when the write callback returns false (sdk/log/batch.go:289-314). Therefore, while the exporter is backpressured, EnqueueExport fails, the queue remains at or above one full batch, and the poll loop continuously retriggers itself without waiting for the ticker.
PoC
The validation artifact contains a PoC bundle:
validation-artifact.tar:main.go: PoC source.- `v…
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-81872 has been found in go.opentelemetry.io/otel/sdk/log.
Attackers can target a specific entry point like BatchingProcessor over the network to misuse the product.
Risk of unauthorized operations or information disclosure.
What to do: upgrade go.opentelemetry.io/otel/sdk/log to 0.21.0 or later.
If unsure, ask your IT team or search "go.opentelemetry.io/otel/sdk/log CVE-2026-81872" on the vendor's site.
CVE-2026-81872 (go.opentelemetry.io/otel/sdk/log) — CWE-400
Attack surface: BatchingProcessor / NewBatchingProcessor / b.q.TryDequeue / b.pollTrigger
Patched: 0.21.0 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-400) exists in go.opentelemetry.io/otel/sdk/log. Attackers reach the vulnerable code path via BatchingProcessor.
Check the vendor advisory for the affected versions of go.opentelemetry.io/otel/sdk/log. Attack surface: BatchingProcessor / NewBatchingProcessor / b.q.TryDequeue / b.pollTrigger.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to 0.21.0.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'go.opentelemetry.io/otel/sdk/log' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
grep -r 'go.opentelemetry.io/otel/sdk/log' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
go.opentelemetry.io/otel/sdk/logを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade go.opentelemetry.io/otel/sdk/log to 0.21.0ステージング環境で 0.21.0 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-81872 golang-opentelemetry-otel
- Ubuntu UBUNTU-CVE-2026-81872 golang-opentelemetry-otel
References
- advisory nvd.nist.gov
- package github.com
- web github.com
- web github.com
- web github.com
- web github.com
- web github.com
- web github.com