What is CVE-2025-1243?

CVE-2025-1243 is a low-severity security vulnerability in go.temporal.io/api (go), affecting versions < 1.44.1. It is fixed in 1.44.1.

Which versions of go.temporal.io/api are affected by CVE-2025-1243?

go.temporal.io/api (go) versions < 1.44.1 is affected.

Is there a fix for CVE-2025-1243?

Yes. CVE-2025-1243 is fixed in 1.44.1. Upgrade to this version or later.

Is CVE-2025-1243 exploitable, and should I be worried?

Whether CVE-2025-1243 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

What actually determines whether CVE-2025-1243 is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

CVE-2025-1243 in go.temporal.io/api

Q: Which versions of go.temporal.io/api are affected by CVE-2025-1243?

go.temporal.io/api (go) versions < 1.44.1 is affected.

Q: Is there a fix for CVE-2025-1243?

Yes. CVE-2025-1243 is fixed in 1.44.1. Upgrade to this version or later.

Q: Is CVE-2025-1243 exploitable, and should I be worried?

Whether CVE-2025-1243 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

Q: What actually determines whether CVE-2025-1243 is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

Q: How do I fix CVE-2025-1243?

Upgrade go.temporal.io/api to 1.44.1 or later.

Summary

Unencrypted transmission in Temporal api-go library

The Temporal api-go library prior to version 1.44.1 did not send update response information to Data Converter when the proxy package within the api-go module was used in a gRPC proxy prior to transmission. This resulted in information contained within the update response field not having Data Converter transformations (e.g. encryption) applied. This is an issue only when using the UpdateWorkflowExecution APIs (released on 13th January 2025) with a proxy leveraging the api-go library before version 1.44.1.

Other data fields were correctly sent to Data Converter. This issue does not impact the Data Converter server. Data was encrypted in transit. Temporal Cloud services are not impacted.

Impact

Affected versions

go.temporal.io/api (< 1.44.1)

Security releases

go.temporal.io/api → 1.44.1 (go)

Kodem intelligence

Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.

Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.

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Remediation advice

Upgrade go.temporal.io/api to 1.44.1 or later to resolve this vulnerability.

Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.

Frequently Asked Questions

What is CVE-2025-1243? CVE-2025-1243 is a low-severity security vulnerability in go.temporal.io/api (go), affecting versions < 1.44.1. It is fixed in 1.44.1.
Which versions of go.temporal.io/api are affected by CVE-2025-1243? go.temporal.io/api (go) versions < 1.44.1 is affected.
Is there a fix for CVE-2025-1243? Yes. CVE-2025-1243 is fixed in 1.44.1. Upgrade to this version or later.
Is CVE-2025-1243 exploitable, and should I be worried? Whether CVE-2025-1243 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
What actually determines whether CVE-2025-1243 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
How do I fix CVE-2025-1243? Upgrade go.temporal.io/api to 1.44.1 or later.