CVE-2026-39882 OpenTelemetry-Go OTLP HTTP exporters read unbounded HTTP response bodies
An attacker controlling the collector endpoint can cause memory exhaustion in OpenTelemetry-Go HTTP exporters by sending unbounded response bodies.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-39882?
CVE-2026-39882 is a medium-severity denial of service vulnerability in open-telemetry opentelemetry-go, published on 8 Apr 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
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.
Weakness: CWE-789
Which versions are affected by CVE-2026-39882?
9 open source packages ship an affected version, including go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp, go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp and go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp Go | All versions | 0.19.0 |
go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp Go | All versions | 0.19.0 |
go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp Go | All versions | 0.19.0 |
go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp Go | All versions | 1.43.0 |
go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp Go | All versions | 1.43.0 |
go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp Go | All versions | 1.43.0 |
3 more packages
go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp Go | All versions | 1.43.0 |
go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp Go | All versions | 1.43.0 |
go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp Go | All versions | 1.43.0 |
Products include Opentelemetry Opentelemetry.
How do I fix CVE-2026-39882?
Upgrade go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp to 0.19.0 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-39882 being exploited?
There is no known exploitation of CVE-2026-39882 in the wild and no public exploit code.
Other vulnerabilities in open-telemetry opentelemetry-go
- CVE-2026-29181 OpenTelemetry-Go multi-value `baggage` header extraction causes excessive allocations (remote dos amplification)
- CVE-2023-47108 DoS vulnerability in otelgrpc (uncontrolled resource consumption) due to unbound cardinality metrics
- CVE-2023-45142 OpenTelemetry-Go Contrib has DoS vulnerability in otelhttp due to unbound cardinality metrics
- CVE-2023-43810 opentelemetry-instrumentation Denial of Service vulnerability due to unbound cardinality metrics
- CVE-2026-39883 opentelemetry-go: BSD kenv command not using absolute path enables PATH hijacking
Sources
Also known as AZL-82082, AZL-82112, AZL-82163, AZL-82190, AZL-82193, AZL-82455 and 735 more.