Vulnerability in Open-Telemetry Opentelemetry-Go

CVE-2026-39882

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.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.002 (7.8th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 8th percentile — 7.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-39882: held from 0.002 to 0.002.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-39882?
CVE-2026-39882 is a medium-severity vulnerability in Open-Telemetry Opentelemetry-Go, classified under CWE-789. CVSS score: 5.3/10. Published 2026-04-08.
How severe is CVE-2026-39882?
Medium severity. CVSS v3 base score is 5.3 out of 10.