fix(remote/azuread): redact OAuth client_secret in config API (CVE-2026-42151)#337
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…26-42151) Backport of upstream prometheus/prometheus#18586 (GHSA-wg65-39gg-5wfj). ClientSecret in OAuthConfig was typed as a plain string, so the value leaked verbatim through the /-/config HTTP endpoint. Switch the field to config.Secret so prometheus/common's MarshalYAML/MarshalJSON implementations redact it to <secret> on serialization; the value is explicitly converted back to string only at the azidentity boundary. Co-authored-by: Cursor <[email protected]>
Signed-off-by: Bastrykov Evgeniy <[email protected]>
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Summary
Backports the upstream Prometheus fix prometheus/prometheus#18586 (GHSA-wg65-39gg-5wfj / CVE-2026-42151) to our fork.
OAuthConfig.ClientSecretinstorage/remote/azureadwas typed as a plainstring, so the value leaked verbatim through the/-/configHTTP API endpoint. Prometheus redacts fields of typeconfig.Secretto<secret>via that type'sMarshalYAML/MarshalJSONmethods; switching the field toSecretplugs the leak. The string value is explicitly recovered only at theazidentity.NewClientSecretCredentialboundary, where a literal string is required.Changes
Why Dependabot couldn't reach this
Alerts #183 and #184 pin the advisory to `pp/tools/block_converter/go.mod` and `documentation/examples/remote_storage/go.mod` — those are offline tools / examples that don't load Azure AD config and don't expose `/-/config`. The actual vulnerable code lives inside our Prometheus fork tree, which Dependabot doesn't watch because we are not an external consumer of `github.com/prometheus/prometheus`. They can be dismissed as `not used` once this PR ships.
Test plan
Made with Cursor