azureauthextension is the Azure Authenticator Extension. From 0.124.0 to 0.150.0, a server-side authentication bypass in azureauthextension allows any party who holds a single valid Azure access token for any scope the collector's configured identity can mint for to authenticate to any OpenTelemetry receiver that uses auth: azure_auth. The extension's Authenticate method does not validate incoming bearer tokens as JWTs. Instead, it calls its own configured credential to obtain an access token and compares the client's token to the result with string equality — and the scope for that server-side token request is taken from the client-supplied Host header. As a result, a token minted for any Azure resource the service principal has ever been issued a token for (ARM, Graph, Key Vault, Storage, etc.) will authenticate to the collector if the attacker picks a matching Host. Tokens are replayable for the full issued lifetime (commonly several hours for managed identity tokens).

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Advisories
Source ID Title
Github GHSA Github GHSA GHSA-pjv4-3c63-699f opentelemetry-collector-contrib's azureauthextension Authenticate method does not validate bearer tokens, allowing auth bypass via replay
Fixes

Solution

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Workaround

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History

Wed, 13 May 2026 20:30:00 +0000

Type Values Removed Values Added
Description azureauthextension is the Azure Authenticator Extension. From 0.124.0 to 0.150.0, a server-side authentication bypass in azureauthextension allows any party who holds a single valid Azure access token for any scope the collector's configured identity can mint for to authenticate to any OpenTelemetry receiver that uses auth: azure_auth. The extension's Authenticate method does not validate incoming bearer tokens as JWTs. Instead, it calls its own configured credential to obtain an access token and compares the client's token to the result with string equality — and the scope for that server-side token request is taken from the client-supplied Host header. As a result, a token minted for any Azure resource the service principal has ever been issued a token for (ARM, Graph, Key Vault, Storage, etc.) will authenticate to the collector if the attacker picks a matching Host. Tokens are replayable for the full issued lifetime (commonly several hours for managed identity tokens).
Title azureauthextension Authenticate method does not validate bearer tokens, allowing auth bypass via replay
Weaknesses CWE-208
CWE-287
CWE-290
CWE-294
CWE-347
References
Metrics cvssV3_1

{'score': 8.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H'}


Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-05-13T20:12:18.936Z

Reserved: 2026-04-29T00:31:15.725Z

Link: CVE-2026-42602

cve-icon Vulnrichment

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cve-icon NVD

Status : Received

Published: 2026-05-13T21:16:47.210

Modified: 2026-05-13T21:16:47.210

Link: CVE-2026-42602

cve-icon Redhat

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cve-icon OpenCVE Enrichment

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