OpenTelemetry eBPF Instrumentation: Unbounded BPF internal metrics replay can exhaust CPU

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

5.9 · CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS

• CVE-2026-45680: 0.32% estimated exploitation activity in the next 30 days; percentile 24.92 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary OBI replays BPF probe hits into histogram observations by looping once per recorded run count. On busy systems, the run-count delta can become very large, causing the metrics exporter to spend excessive CPU time in a tight loop every collection interval. Details The vulnerable loop is in pkg/export/prom/prombpf.go. During each metrics tick, OBI iterates through probeMetrics and then executes for range metric.count, invoking BpfProbeLatency(...) for each individual recorded hit. The count comes from calculateStats() in the same file, where deltaCount := bp.runCount - bp.prevRunCount is calculated and returned without any cap before the per-hit replay loop. If probe activity spikes between scrape intervals, deltaCount can be very large. The exporter then spends CPU time proportional to the number of probe hits rather than the number of metric series. PoC Local testing with a small reproducer confirmed the replay-loop behavior and showed CPU scaling with the recorded hit count…

Published by the source

18 May 2026, 20:11 UTC

Last modified by the source

9 Jun 2026, 10:58 UTC

Source last checked

26 Oct 2026, 15:23 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-89c6-vpcj-7vj4

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# Patch Next advisory brief: CVE-2026-45680

Advisory: OpenTelemetry eBPF Instrumentation: Unbounded BPF internal metrics replay can exhaust CPU
IDs: CVE-2026-45680, GHSA-89c6-vpcj-7vj4
Record: https://patchnext.com/advisories/cve-2026-45680 (revision 1, source checked 26 Oct 2026, 15:23 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.9)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: go.opentelemetry.io/obi 0.9.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go go.opentelemetry.io/obi: affected < 0.9.0; fixed in 0.9.0

## Suggested inspection (read-only)
- Go go.opentelemetry.io/obi: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on go.opentelemetry.io/obi.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-89c6-vpcj-7vj4 (GitHub-reviewed advisory GHSA-89c6-vpcj-7vj4 lists affected ranges: Go go.opentelemetry.io/obi >=0 <0.9.0)

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