CVE-2026-48892: Apache Airflow Config API Secrets Exposure (MEDIUM)

Technical summary

CVE-2026-48892 is an information disclosure vulnerability in Apache Airflow's configuration masking layer. The issue stems from how Airflow processes per-key secrets-backend override environment variables (e.g., `AIRFLOW__SECRETS__BACKEND_KWARG__SECRET_ID`, `AIRFLOW__WORKERS__SECRETS_BACKEND_KWARG__SECRET_ID`). These environment variables are synthesized into configuration options at runtime, but their option names were omitted from the `sensitive_config_values` list that drives the masking function. Consequently, when the Config API returns configuration snapshots, these keys appear with plaintext values instead of redacted masks. An authenticated principal with Config-read permissions can enumerate and retrieve exposed credentials, including Vault role_id/secret_id pairs and similar backend-specific authentication material.

Business impact

This vulnerability creates a credential exposure risk for any Airflow deployment using environment-variable-based secrets-backend configuration. Exposed secrets-backend credentials could allow attackers—especially insiders or threat actors who compromise an Airflow UI/API account—to authenticate directly to external secret stores (Vault, AWS Secrets Manager, etc.), potentially accessing the entire credential corpus that Airflow manages. This circumvents the intended isolation where Airflow acts as a single point of trust. For organizations relying on Vault or similar systems as their enterprise credential backbone, the blast radius extends beyond Airflow workflows to any system trusting those same credentials.

Affected systems

Apache Airflow deployments affected by this issue must satisfy two conditions: (1) the deployment must authenticate users and expose the Config API via UI or programmatic endpoints, and (2) administrators must configure secrets backends using per-key environment variable overrides rather than monolithic backend configuration. Airflow 3.3.0 and later resolve the issue. All versions prior to 3.3.0 that use this configuration pattern are vulnerable.

Exploitability

The vulnerability requires prior authentication to Airflow. An attacker cannot exploit this anonymously; they must possess valid credentials and the Config-read permission (a standard permission in many RBAC setups). Once authenticated, exploitation is trivial—invoking the Config API and parsing plaintext credential values requires minimal effort. There is no known public exploit code, and the issue is not yet listed on CISA's Known Exploited Vulnerabilities catalog, suggesting limited real-world weaponization to date. However, the simplicity of exploitation and the high value of secrets-backend credentials make this an attractive target for insider threats or post-compromise credential harvesting.

Remediation

Upgrade Apache Airflow to version 3.3.0 or later, which restores proper masking of secrets-backend override environment variables. Before upgrading, administrators should rotate any secrets-backend credentials (e.g., Vault role_id/secret_id) that may have been exposed via the Config API. Audit Airflow user permissions and restrict Config-read access to trusted administrative accounts. Consider migrating sensitive backend credentials from environment variables to Airflow's native secrets-backend abstraction without per-key overrides, or to encrypted secret stores outside of environment configuration.

Patch guidance

Apache Airflow 3.3.0 and later include the fix. Verify the availability of this version through the official Apache Airflow release channels and test in a staging environment before production deployment. Organizations unable to upgrade immediately should enforce strict access controls on the Config API (e.g., IP allowlisting, network segmentation) and audit API access logs for unauthorized Config-read operations. Monitor for suspicious authentication or lateral movement from accounts that have accessed configuration endpoints.

Detection guidance

Look for authenticated API calls to Airflow's Config endpoints (typically `/api/v1/config`) or UI navigation to configuration pages, especially from service accounts or non-administrative users. Examine API response logs for plaintext credential patterns (e.g., base64-encoded or raw `role_id`, `secret_id` strings in JSON output). Check environment variable configurations in deployment manifests or pod specs for `AIRFLOW__*__SECRETS_BACKEND_KWARG__*` keys. Alert on any export or download of configuration data by non-admin users. Compare current Airflow versions against 3.3.0 to identify unpatched instances.

Why prioritize this

Although this vulnerability requires authentication and is rated MEDIUM (CVSS 6.5), the nature of the exposed data—cryptographic credentials to enterprise secret backends—makes it a high-priority fix. A single compromised Airflow user account or insider could leak organization-wide secrets. The fix is straightforward (upgrade to 3.3.0), and the risk of delayed remediation includes downstream compromise of systems that trust the exposed secrets-backend credentials. Organizations should prioritize patching within 2–4 weeks, sooner if Airflow is accessible to contract workers or federated users.

Risk score, explained

The CVSS 6.5 MEDIUM score reflects the requirement for authentication (PR:L) and the confidentiality-only impact (C:H). However, the true risk is amplified by the sensitivity of secrets-backend credentials, which often grant access to critical infrastructure secrets. The score appropriately discounts unauthenticated attacks but does not fully capture the downstream harm of exposed Vault or Secrets Manager credentials. Organizations should treat this as a high-priority fix despite the MEDIUM rating.

Frequently asked questions