CVE-2026-45681 OpenTelemetry eBPF Instrumentation: CPU-mismatch fallback uses 256-byte buffer with 8KB size
An attacker can trigger a CPU mismatch to leak adjacent memory into telemetry data via a buffer size mismatch in the fallback path.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-45681?
CVE-2026-45681 is a medium-severity vulnerability in open-telemetry opentelemetry-ebpf-instrumentation, published on 2 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
OpenTelemetry eBPF Instrumentation provides eBPF instrumentation based on the OpenTelemetry standard. Prior to version 0.9.0, the per-CPU message-buffer fallback path uses a 256-byte backup buffer but preserves the original payload size, which can be up to 8KB. If a CPU mismatch occurs, OBI can read beyond the fallback buffer and leak adjacent memory into telemetry. This issue has been patched in version 0.9.0.
Which versions are affected by CVE-2026-45681?
3 open source packages ship an affected version, including go.opentelemetry.io/obi. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
go.opentelemetry.io/obi Go | All versions | 0.9.0 |
go.opentelemetry.io/obi Go | All versions | 0.9.0 |
go.opentelemetry.io/obi Go | All versions | 0.9.0 |
Products include Opentelemetry Ebpf Instrumentation.
How do I fix CVE-2026-45681?
Upgrade go.opentelemetry.io/obi to 0.9.0 or later.
Is CVE-2026-45681 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-45681 exists.
Other vulnerabilities in open-telemetry opentelemetry-ebpf-instrumentation
- CVE-2026-45678 OpenTelemetry eBPF Instrumentation: Postgres BIND parsing can panic on malformed payloads
- CVE-2026-45685 OpenTelemetry eBPF Instrumentation: MongoDB parser panics on malformed wire messages
- CVE-2026-45686 OpenTelemetry eBPF Instrumentation: Memcached payload length overflow can crash OBI
- CVE-2026-45679 OpenTelemetry eBPF Instrumentation: Redis error text is exported in span status messages
- CVE-2026-45680 OpenTelemetry eBPF Instrumentation: Unbounded BPF internal metrics replay can exhaust CPU
Sources
Also known as GHSA-r6c9-g6q5-qrf9, GO-2026-5610.