Prometheus Azure AD remote write OAuth client secret exposed via config API
### Impact Users who use Azure AD remote write with OAuth authentication are impacted. 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. ### Patches The problem has been patched by changing `ClientSecret` in `OAuthConfig` to `Secret`. Users should upgrade to 3.11.3 or 3.5.3 LTS. ### Workarounds Users who can not upgrade can switch to Managed Identity or Workload Identity authentication for Azure AD remote write, which do not involve a client secret.
02 / AFFECTED SOFTWARE
Affected packages
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
### Impact Users who use Azure AD remote write with OAuth authentication are impacted. 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. ### Patches The problem has been patched by changing `ClientSecret` in `OAuthConfig` to `Secret`. Users should upgrade to 3.11.3 or 3.5.3 LTS. ### Workarounds Users who can not upgrade can switch to Managed Identity or Workload Identity authentication for Azure AD remote write, which do not involve a client secret.
Prometheus Azure AD remote write OAuth client secret exposed via config API in github.com/prometheus/prometheus
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.
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.
05 / REFERENCES
Further evidence
- https://github.com/prometheus/prometheus
- 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
- https://github.com/prometheus/prometheus/security/advisories/GHSA-wg65-39gg-5wfj
- https://nvd.nist.gov/vuln/detail/CVE-2026-42151
- https://access.redhat.com/errata/RHSA-2026:25039
- https://access.redhat.com/errata/RHSA-2026:25245
- https://access.redhat.com/errata/RHSA-2026:25504
- https://access.redhat.com/errata/RHSA-2026:34357
- https://access.redhat.com/errata/RHSA-2026:34359
- https://access.redhat.com/errata/RHSA-2026:36651
- https://access.redhat.com/errata/RHSA-2026:36796
- https://access.redhat.com/errata/RHSA-2026:36797
- https://access.redhat.com/errata/RHSA-2026:37267
- https://access.redhat.com/errata/RHSA-2026:37271
- https://access.redhat.com/errata/RHSA-2026:37272
- https://access.redhat.com/errata/RHSA-2026:40118
- https://access.redhat.com/errata/RHSA-2026:40262
- https://access.redhat.com/errata/RHSA-2026:40768
- https://access.redhat.com/errata/RHSA-2026:40945
- https://access.redhat.com/errata/RHSA-2026:40970
- https://access.redhat.com/errata/RHSA-2026:40972
- https://access.redhat.com/errata/RHSA-2026:40974
- https://access.redhat.com/errata/RHSA-2026:41019
- https://access.redhat.com/errata/RHSA-2026:41030
- https://access.redhat.com/errata/RHSA-2026:41031
- https://access.redhat.com/errata/RHSA-2026:41066
- https://access.redhat.com/errata/RHSA-2026:42146
- https://access.redhat.com/errata/RHSA-2026:42796
- https://access.redhat.com/errata/RHSA-2026:42852
- https://access.redhat.com/errata/RHSA-2026:43052
- https://access.redhat.com/errata/RHSA-2026:44622
- https://access.redhat.com/errata/RHSA-2026:47149
- https://access.redhat.com/errata/RHSA-2026:47952
- https://access.redhat.com/errata/RHSA-2026:50843
- https://access.redhat.com/errata/RHSA-2026:50874
- https://access.redhat.com/errata/RHSA-2026:53412
- https://access.redhat.com/errata/RHSA-2026:53413
- https://access.redhat.com/errata/RHSA-2026:53415
- https://access.redhat.com/errata/RHSA-2026:53530
- https://access.redhat.com/errata/RHSA-2026:54288
- https://access.redhat.com/errata/RHSA-2026:54427
- https://access.redhat.com/errata/RHSA-2026:56340
- https://access.redhat.com/security/cve/CVE-2026-42151
- https://bugzilla.redhat.com/show_bug.cgi?id=2466507
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42151.json
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42151.json