Vulnerability · Published Apr 10, 2026 · Assigned by Temporal
CVE-2026-5724Missing Authentication on Streaming gRPC Replication Endpoint
Medium 6.3
In plain English
A medium-severity missing authentication in temporal from Temporal Technologies, Inc.. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 45% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code. Fixed versions are available - upgrade the affected package.
Official description
The frontend gRPC server's streaming interceptor chain did not include the authorization interceptor. When a ClaimMapper and Authorizer are configured, unary RPCs enforce authentication and authorization, but the streaming AdminService/StreamWorkflowReplicationMessages endpoint accepted requests without credentials. This endpoint is registered on the same port as WorkflowService and cannot be disabled independently. An attacker with network access to the frontend port could open the replication stream without authentication. Data exfiltration is possible, but only when a configured replication target is correctly configured and the attacker has knowledge of the cluster configuration, as the history service validates cluster IDs and peer membership before returning replication data. The fix was applied per release line: it is present in 1.28.4, 1.29.6, 1.30.4, 1.31.2, and 1.32.0 and later releases on each line. Releases 1.31.0 and 1.31.1 do not contain the fix and are affected. Temporal Cloud is not affected.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | go.temporal.io/server | 1.28.4 | GHSA-q98v-9f9w-f49q |
| Go | go.temporal.io/server | 1.29.6 | GHSA-q98v-9f9w-f49q |
| Go | go.temporal.io/server | 1.30.4 | GHSA-q98v-9f9w-f49q |
| Go | go.temporal.io/server | 1.28.4, 1.29.6, 1.30.4 | GO-2026-5578 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Temporal Technologies, Inc. | temporal | 1.24.0 – before 1.28.41.29.0 – before 1.29.61.30.0 – before 1.30.41.31.0 – before 1.31.2 |
Weakness: CWE-306 · Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/SC:L/SI:N/SA:N/S:N/AU:N/R:U/RE:L