VulnerabilityAwaiting Analysis

CVE-2026-5724

An attacker with network access to the frontend port could open the replication stream without authentication.

MEDIUM 6.3EPSS 0.53%

Does this matter?

Lower severity and a low EPSS score (0.53%). Track it; it rarely justifies an emergency change on its own.

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.

CVSS 4.0: 6.3 MEDIUMCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/SC:L/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS: 0.53% probability · 43th percentile
CISA KEV: Not listed
Weakness: CWE-306
Source: security@temporal.io

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.