OpenTelemetry eBPF Instrumentation: Memcached payload length overflow can crash OBI

Exploitation

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

CVSS

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

EPSS

• CVE-2026-45686: 0.35% estimated exploitation activity in the next 30 days; percentile 29.13 (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 A remotely reachable integer overflow in OBI's memcached text protocol parser can crash the OBI process and cause denial of service. When parsing memcached storage commands such as set, add, replace, append, prepend, or cas, OBI accepts extremely large <bytes values and adds the payload delimiter length without checking for overflow. A crafted request with <bytes set to math.MaxInt or math.MaxInt-1 causes the computed payload length to wrap negative and triggers a runtime panic in LargeBufferReader.Peek. Details The issue is in the memcached request parser at pkg/ebpf/common/memcacheddetecttransform.go. memcachedCommandBytesField parses the storage command <bytes field with strconv.Atoi and only rejects negative values: Because there is no upper bound check, values up to math.MaxInt are accepted. memcachedConsumeStoragePayload then computes the payload length by adding the trailing \r\n delimiter length: If bytesField is math.MaxInt or math.MaxInt-1, this addition overflows…

Published by the source

18 May 2026, 20:21 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-43g7-cwr8-q3jh

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# Patch Next advisory brief: CVE-2026-45686

Advisory: OpenTelemetry eBPF Instrumentation: Memcached payload length overflow can crash OBI
IDs: CVE-2026-45686, GHSA-43g7-cwr8-q3jh
Record: https://patchnext.com/advisories/cve-2026-45686 (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: High (CVSS 7.5)
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 >= 0.7.0, < 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-43g7-cwr8-q3jh (GitHub-reviewed advisory GHSA-43g7-cwr8-q3jh lists affected ranges: Go go.opentelemetry.io/obi >=0.7.0 <0.9.0)

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