Medium severity · published May 26, 2026
CVE-2026-44213
OpenTelemetry.Exporter.Instana bypasses TLS certificate validation when a proxy is configured
6.5
CVSS
0.2%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
None
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 11% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OP
opentelemetry-dotnet-contrib · open-telemetry
< 1.1.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-44213
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-44213
github.com
https://github.com/open-telemetry/opentelemetry-dotnet-contrib/security/advisories/GHSA-wfr5-454p-mjc2
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