Valtimo has sensitive data exposure through HTTP request/response logging in LoggingRestClientCustomizer

Summary

The LoggingRestClientCustomizer in the web module automatically intercepts all outgoing HTTP calls made via Spring's RestClient and logs the full request body, response body, and response headers. When an error response is received, this information is included in the thrown HttpClientErrorException message, which is logged at ERROR level by Spring's default exception handling — regardless of the application's DEBUG log level setting.

Impact

The logged data can contain highly sensitive information including:

• Authentication credentials (JWT tokens, API keys, OAuth tokens) in request bodies or response headers
• Personal data (BSN, email addresses, case details) in request/response bodies
• Session tokens in Set-Cookie response headers

This data is exposed to:

• Anyone with access to application logs (stdout/log files)
• Users with access to logging aggregation tools (e.g. Grafana/Loki)
• Any Valtimo user with the admin role, through the built-in logging module (since Valtimo 12.5.0)

Leaked authentication credentials could be used to impersonate the Valtimo application against the target external API (e.g. ZGW services), compromising that API's security boundary.

Related: GHSA-hfrg-mcvw-8mch (similar sensitive data exposure in InboxHandlingService)

Affected Code

com.ritense.valtimo.web.logging.LoggingRestClientCustomizer#intercept in the web module.

Patched Versions

The vulnerability is fixed in:

• 12.33.0 (v12 release line) — see PR #600
• 13.26.0 (v13 release line) — see PR #599

The fix removes the request/response report, headers, and response body from the HttpClientErrorException constructor; only the HTTP status code and status text remain. The full request/response report is still emitted at DEBUG level (disabled in production).

Mitigation

If you cannot upgrade to a patched version immediately, consider:

• Restricting access to application logs and the Valtimo logging module
• Adjusting the log level for com.ritense.valtimo.web.logging to WARN or higher (note: this only mitigates the DEBUG logging path; error responses still leak data via the exception message)