CVE-2026-44213: open-telemetry opentelemetry-dotnet-contrib · Improper Certificate Validation
Affects open-telemetry opentelemetry-dotnet-contribSource CVE Database V5
Not known to be exploited · CVSS 6.5 Medium : upgrade to 1.1.0 when convenient.
Data as of 30 Oct 2026, 06:59 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 10% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 1.1.0
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:NExploitation evidence
Disclosed: evidence found.
CVE published 26 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Upgrade opentelemetry-dotnet-contrib and opentelemetry.exporter.instana to 1.1.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| open-telemetryopentelemetry-dotnet-contrib | Affected
| Fixed in
|
NuGetopentelemetry.exporter.instanapkg:nuget/opentelemetry.exporter.instanaOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade the OpenTelemetry.Exporter.Instana NuGet package to version 1.1.0 or later, where this certificate validation issue is fixed. Avoid using vulnerable versions (<1.1.0) especially in environments where proxy usage is configured via INSTANA_ENDPOINT_PROXY. Patch status is not explicitly confirmed in a vendor advisory, so check the vendor's official sources for the latest remediation guidance.
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.