6.5

CVE-2026-44213: open-telemetry opentelemetry-dotnet-contrib Improper Certificate Validation

CVSS: 6.5v3.1MediumAwaiting analysis
AliasesGHSA-wfr5-454p-mjc2
Published 26-05-2026Last modified 27-05-2026
Open JSON

Vulnerability summary

CVE-2026-44213 is a medium (CVSS 6.5) Improper Certificate Validation vulnerability in open-telemetry opentelemetry-dotnet-contrib. EPSS estimates a 0.24% chance of exploitation in the next 30 days, higher than 14.3% of scored vulnerabilities.

Overall risk
26/100
0100
Medium · default modelHow is this calculated?
CVSS score
6.5/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.24%
0%100%
Low · +0.03 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 26-05-2026
    PublishedVulnerability first disclosed.
  2. 27-05-2026
    Last modifiedVulnerability information updated.

Description

The OpenTelemetry.Exporter.Instana exports telemetry to Instana backend. Prior to 1.1.0, the OpenTelemetry.Exporter.Instana NuGet package does not validate HTTPS/TLS certificates are valid when sending telemetry to a configured Instana back-end when a proxy is configured using the INSTANA_ENDPOINT_PROXY environment variable. If a network attacker can Man-in-the-Middle (MitM) the proxy connection, all OpenTelemetry telemetry data and the Instana API key are exposed to the attacker. This vulnerability is fixed in 1.1.0.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.24%

Chance of exploitation in the next 30 days

Percentile

14%

Versus all other CVEs

30-day change

+0.03 pp

From 0.21% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.24%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

NuGet1 product
  • OpenTelemetry.Exporter.Instana< 1.1.0
Open-telemetry1 product

2 vendors · 2 products

References

3 links