Temporal has a namespace policy bypass allowing requests to be authorized for incorrect contexts

Description

When frontend.enableExecuteMultiOperation is enabled, the server can apply namespace-scoped validation and feature gates for the embedded StartWorkflowExecutionRequest using its Namespace field rather than the outer, authorized ExecuteMultiOperationRequest.Namespace. This allows a caller authorized for one namespace to bypass that namespace's limits/policies by setting the embedded start request's namespace to a different namespace. The workflow is still created in the outer (authorized) namespace; only validation/gating is performed under the wrong namespace context.
This issue affects Temporal: from 1.24.0 through 1.29.1. Fixed in 1.27.4, 1.28.2, 1.29.2.

Basic information

Type
reviewed
Severity
low
Advisory on GitHub
Open advisory ↗
Repository advisory
Source code
Browse source ↗
Published (advisory)
2025-12-30 21:30:33 UTC
Updated
2025-12-31 22:08:25 UTC
GitHub reviewed
2025-12-31 22:08:24 UTC
NVD published
2025-12-30

EPSS Score

Score Percentile
0.03% 6.58%

CVSS Scores

Base score Version Severity Vector
1.3 4.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network.
Attack complexity (AC:L)
Exploitation conditions are straightforward and stable.
Attack requirements (AT:N)
No additional preconditions are required beyond normal reachability.
Privileges required (PR:L)
Low privileges are required.
User interaction (UI:N)
No user interaction is required.
Vulnerable system confidentiality impact (VC:N)
No confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:L)
Limited integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:N)
No availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:N)
No confidentiality impact on subsequent systems.
Subsequent system integrity impact (SI:N)
No integrity impact on subsequent systems.
Subsequent system availability impact (SA:N)
No availability impact on subsequent systems.
Exploit maturity (threat) (E:U)
Unreported: no public PoC, no reported exploitation, and no known simplification tools.

Identifiers

CWEs

CWE id Name
CWE-863 Incorrect Authorization

Affected packages (3)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
go go.temporal.io/server >= 1.24.0, < 1.27.4 1.27.4
go go.temporal.io/server >= 1.28.0, < 1.28.2 1.28.2
go go.temporal.io/server >= 1.29.0, < 1.29.2 1.29.2

References

cvelogic Threat Intelligence