CVE-2026-89140: Temporal Server 1.30.0 to before 1.30.8, 1.31.0 to before 1.31.4, 1.32.0 to before 1.32.1

Affected technology

Temporal Server · 1.30.0 to before 1.30.8
Temporal Technologies, Inc.

Temporal Server · 1.31.0 to before 1.31.4
Temporal Technologies, Inc.

Temporal Server · 1.32.0 to before 1.32.1
Temporal Technologies, Inc.

Component: Frontend, History
Function: WorkflowHandler.validateWorkflowCompletionCallbacks, WorkflowHandler.validateCallbackURL, AddressMatchRules.Validate, chasmInvocation.Invoke, Handler.CompleteNexusOperationChasm, Scheduler.HandleNexusCompletion, invocableInternal.Invoke, WorkflowHandler.prepareStartWorkflowRequest, validator.Validate
File: service/frontend/workflow_handler.go, components/callbacks/config.go, components/callbacks/executors.go, components/callbacks/chasm_invocation.go, service/history/handler.go, chasm/lib/scheduler/scheduler.go, chasm/lib/callback/invocable_internal.go, chasm/lib/callback/validator.go, chasm/lib/callback/config.go

Attack conditions (Vendor/CNA, CVSS 4.0): Network (remote) · Low privileges required · No user interaction required

What an attacker can do

Vendor/CNA’s CVSS 4.0 assessment (base score 6.0/10) rates confidentiality and availability impact as none; integrity impact as high. The description does not specify what an attacker can achieve beyond these rated impacts.