How severe is CVE-2025-14987?

No CVSS score has been assigned to CVE-2025-14987 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2025-14987?

CVE-2025-14987 affects the following packages: go.temporal.io/server (Go), go.temporal.io/server (Go), go.temporal.io/server (Go), go.temporal.io/server (Go). Ecosystems affected: Go.

How do I fix CVE-2025-14987?

Update go.temporal.io/server to 1.27.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-14987 is resolved across your whole dependency graph.

How do I detect CVE-2025-14987 in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for go.temporal.io/server, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2025-14987 if there is no patch (or I can't update yet)?

Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.

Is CVE-2025-14987 actively exploited in the wild?

No public exploit code has been indexed for CVE-2025-14987 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2025-14987?

CVE-2025-14987 has an EPSS (Exploit Prediction Scoring System) score of 0.4%, placing it in the 34th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2025-14987?

CVE-2025-14987 is classified as CWE-863 (CWE-863). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2025-14987 published, and has it been updated?

CVE-2025-14987 was published on December 30, 2025 and was last updated on October 28, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐹 Go

Not in CISA KEV

CVE-2025-14987 — server

Fix: temporalio/temporal@b292a32

CVE-2025-14987 is a CWE-863 vulnerability in go.temporal.io/server. A fix is available for go.temporal.io/server — see the affected versions and patch details below.

Cross Namespace Commands Authorization Bypass

Also known asGHSA-hmhp-gh8m-c8xpGO-2026-4273

Published

Dec 30, 2025

Updated

Oct 28, 2026

Affected

4 pkgs

Patched

4 / 4

Exploits

None indexed

Exploitation data as of Nov 3, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2025-14987.

EPSS Exploitation Probability

via FIRST.org ↗

0.4%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs34th percentile — riskier than 34% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

4 pkgs affected

🐹go.temporal.io/server🐹go.temporal.io/server🐹go.temporal.io/server🐹go.temporal.io/server

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.

Description

When system.enableCrossNamespaceCommands is enabled (on by default), the Temporal server permits certain workflow task commands (e.g. StartChildWorkflowExecution, SignalExternalWorkflowExecution, RequestCancelExternalWorkflowExecution) to target a different namespace than the namespace authorized at the gRPC boundary. The frontend authorizes RespondWorkflowTaskCompleted based on the outer request namespace, but the history service later resolves and executes the command using the namespace embedded in command attributes without authorizing the caller for that target namespace. This can allow a worker authorized for one namespace to create, signal, or cancel workflows in another namespace. This issue affects Temporal: through 1.29.1. Fixed in 1.27.4, 1.28.2, 1.29.2.

Affected Packages

4 total 4 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`go.temporal.io/server`	all versions	1.27.4`go get go.temporal.io/server@v1.27.4`
🐹Go	`go.temporal.io/server`	≥ 1.28.0&&< 1.28.2	1.28.2`go get go.temporal.io/server@v1.28.2`
🐹Go	`go.temporal.io/server`	≥ 1.29.0&&< 1.29.2	1.29.2`go get go.temporal.io/server@v1.29.2`
🐹Go	`go.temporal.io/server`	≥ 1.29.0-0&&< 1.29.0-135.0.0.20251218190115-b292a32bacdf	1.29.0-135.0.0.20251218190115-b292a32bacdf`go get go.temporal.io/server@v1.29.0-135.0.0.20251218190115-b292a32bacdf`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for go.temporal.io/server, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update go.temporal.io/server to 1.27.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-14987 is resolved across your whole dependency graph.
Workarounds
Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.