CVE-2026-44967: OpenTelemetry-cpp memory exhaustion in OTLP HTTP exporters

CVE-2026-44967 · Severity: medium · CVSS 5.3 · Published 2026-06-12

OpenTelemetry-cpp is a library used by developers to monitor application performance by sending data to a central collector. A vulnerability in the library's communication component allows a malicious or compromised data collector to send an oversized response that crashes the monitored application. This could lead to service outages if the application is configured to send data to an untrusted endpoint or if a network attacker intercepts the connection.

Vendors: Opentelemetry.

Quick answers

Is CVE-2026-44967 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-44967 being exploited in the wild.
How severe is CVE-2026-44967?
Medium severity, with a CVSS score of 5.3, published 12 June 2026.
Which products and versions are affected?
Opentelemetry-Cpp < 1.27.0.
Is there a fix for CVE-2026-44967?
A patch was published on 2026-05-12: Fix merged into main branch Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-44967 attacked?
It is attacked from the adjacent network, in a software library.
Am I affected by CVE-2026-44967?
Check whether you run Opentelemetry-Cpp at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The OTLP HTTP exporters (traces, metrics, and logs) in OpenTelemetry-cpp prior to version 1.27.0 fail to enforce a size limit when reading HTTP response bodies. The library reads the full response into an in-memory byte vector, which is then copied into a string, leading to excessive memory allocation. An attacker who controls the collector endpoint or can perform a Man-in-the-Middle (MitM) attack can provide a massive response body to trigger an Out-of-Memory (OOM) condition and crash the process. This is classified as CWE-789 (Memory Allocation with Excessive Size Value). The issue is resolved in version 1.27.0 by implementing maximum size limits in the CURL-based HTTP client.

Affected products

  • OpenTelemetry opentelemetry-cpp < 1.27.0

Timeline

  • 2026-03-30: other: Issue first reported on GitHub
  • 2026-05-12: patched: Fix merged into main branch
  • 2026-05-18: advisory: GitHub Security Advisory published
  • 2026-06-12: disclosed: CVE published to NVD

References

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