CVE-2026-42151Network attack vector

OAuth secret disclosure via unredacted configuration field

Published May 4, 2026 · Updated May 4, 2026

Information disclosure in Prometheus before 3.5.3 and 3.6.0 through 3.11.2 allows remote attackers to read an Azure OAuth secret. The storage/remote/azuread OAuthConfig declares ClientSecret as a plain string, so the /-/config response bypasses Secret-field redaction and returns the value in plaintext. Exposure requires Azure AD remote write with OAuth authentication and access to the configuration endpoint; the disclosed credential enables unauthorized use of the configured Azure application.

CVSS severity7.5
High
EPSS probability0.35%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in Prometheus before 3.5.3 and 3.6.0 through 3.11.2 allows remote attackers to read an Azure OAuth secret. The storage/remote/azuread OAuthConfig declares ClientSecret as a plain string, so the /-/config response bypasses Secret-field redaction and returns the value in plaintext. Exposure requires Azure AD remote write with OAuth authentication and access to the configuration endpoint; the disclosed credential enables unauthorized use of the configured Azure application.

The record

CVE
CVE-2026-42151
Published
May 4, 2026
Updated
May 4, 2026
Vendor
Prometheus
Product
Prometheus
Classifications
CWE-200, CWE-312, T1552
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 4, 2026CVE publishedPublication date reported by the CVE source.
  2. May 4, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 3.5.3
  2. Affected versionversion=>= 3.6.0, < 3.11.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Prometheus · Prometheusversion=< 3.5.3; version=>= 3.6.0, < 3.11.3

Published CVSS scores

7.5GitHubCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-200Exposure of Sensitive Information to an Unauthorized Actor
CWE-312Cleartext Storage of Sensitive Information
T1552Unsecured Credentials

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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