CVE-2026-31377: Improper Authentication in Apache Doris FE Meta Service
An Improper Authentication vulnerability, tracked as CVE-2026-31377, has been disclosed in the Apache Doris Frontend (FE) meta service. The flaw, rated 7.5 (High) on the CVSS 3.1 scale, allows an unauthenticated remote attacker to access internal metadata service endpoints. The affected endpoints trusted client-supplied node information as a stand-in for authentication, without independently verifying the identity of the requesting party. The vulnerability was published September 23, 2026 by the Apache Software Foundation.
Details
| Attribute | Value |
|---|---|
| CVE ID | CVE-2026-31377 |
| CVSS Score | 7.5 (High) — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |
| Severity | High |
| Affected Product | Apache Doris — Frontend (FE) meta service |
| Affected Versions | 2.0.0 through 4.0.7; 4.1.0 through 4.1.3; all 2.1.x, 3.0.x, and 3.1.x releases |
| Fixed Versions | 4.0.8 and 4.1.4 |
| Unaffected | 1.2.x and earlier |
| Vulnerability Type | Improper Authentication (CWE-287) |
| Published | September 23, 2026 |
What Happened
Apache Doris is an open-source, MPP-based real-time analytics database widely used for OLAP workloads. Its Frontend (FE) nodes expose a meta service used internally to exchange cluster and node metadata between components.
According to the project's own security advisory, the affected meta service endpoints relied on client-supplied node information for authentication rather than independently validating the identity of the calling party. In practice, this means a request could assert its own identity (e.g., claim to be a trusted internal FE node) without the service cryptographically or otherwise verifying that claim.
Technical Details
- The root cause is classified as CWE-287: Improper Authentication — the meta service's trust model accepted attacker-controllable input as an authentication signal.
- Because the check is on client-supplied data rather than a verified credential, an attacker who can reach the meta service endpoint over the network does not need valid credentials, a session token, or any prior access to the cluster.
- The Apache Doris project notes that exploitability is conditioned on network configuration — deployments where the FE meta service is reachable from untrusted networks (rather than isolated to a trusted internal segment) are the ones exposed to remote exploitation.
- The vulnerability affects Apache Doris 2.0.0 through 4.0.7 and 4.1.0 through 4.1.3, including all 2.1.x, 3.0.x, and 3.1.x releases. Versions 1.2.x and earlier are not affected, as this header-trust pattern was introduced later in the codebase.
- No public proof-of-concept exploit code has been identified, and no active exploitation in the wild had been confirmed as of publication.
Impact Assessment
| Impact Area | Description |
|---|---|
| Confidentiality | High — unauthenticated access to internal FE metadata interfaces can expose sensitive cluster configuration and topology information (CVSS impact: C:H) |
| Integrity | None reported in this CVE — the advisory describes read access to metadata, not modification (I:N) |
| Availability | None reported in this CVE (A:N) |
| Attack Complexity | Low — no special conditions required beyond network reachability (AC:L) |
| Privileges Required | None (PR:N) |
| User Interaction | None (UI:N) |
| Exposure Scope | Deployments with the FE meta service reachable from untrusted or semi-trusted networks carry the greatest risk |
Recommendations
For Administrators Running Apache Doris
- Upgrade to a fixed release — Apache Doris 4.0.8 or 4.1.4 resolves this issue. Confirm your deployed version against the affected ranges above and prioritize patching for any internet-facing or multi-tenant clusters.
- Inventory your Doris deployments — identify every FE node and meta service instance in your environment, including staging and internal analytics clusters that may be lower priority for patch cycles but still network-reachable.
For Security Teams
- Restrict network exposure as an interim mitigation where immediate patching is not possible — the FE meta service should only be reachable from trusted internal segments (other FE/BE cluster nodes), never from general application networks or the internet.
- Review firewall and security group rules for Doris FE ports to confirm they are not inadvertently exposed beyond the cluster's trust boundary.
- Audit access logs on FE meta service endpoints for unexpected source IPs or requests asserting node identities that do not match your known cluster topology.
- Track the related advisories disclosed alongside this one — Apache also published CVE-2026-58319 (unauthenticated access to FE HTTP administrative APIs, fixed in 3.1.0) and CVE-2026-72524 (incorrect authorization allowing privilege-check bypass, fixed in 4.0.8/4.1.4) — organizations running affected Doris versions should evaluate all three.
For End Users / Downstream Consumers
- If your organization consumes data from a managed or third-party Doris-backed analytics service, confirm with your provider that patched versions are in use.
Key Takeaways
- CVE-2026-31377 is a High-severity (CVSS 7.5) improper authentication flaw in the Apache Doris FE meta service, allowing unauthenticated remote access to internal metadata endpoints.
- The root cause is a trust-the-client authentication pattern — the service accepted client-supplied node information instead of independently verifying requester identity.
- Versions 2.0.0–4.0.7 and 4.1.0–4.1.3 are affected (including all 2.1.x, 3.0.x, 3.1.x releases); 1.2.x and earlier are not affected.
- Fixed versions are 4.0.8 and 4.1.4 — administrators should upgrade as soon as operationally feasible.
- No active exploitation or public PoC has been reported as of the September 23, 2026 disclosure, but network exposure of the FE meta service is the key risk factor.
- Until patched, restricting network access to the FE meta service to trusted cluster nodes only is the primary available mitigation.