What is CVE-2025-57349?

CVE-2025-57349 is a low-severity security vulnerability in messageformat (npm), affecting versions < 2.3.0. It is fixed in 3.0.0-beta.0.

Which versions of messageformat are affected by CVE-2025-57349?

messageformat (npm) versions < 2.3.0 is affected.

Is there a fix for CVE-2025-57349?

Yes. CVE-2025-57349 is fixed in 3.0.0-beta.0. Upgrade to this version or later.

Is CVE-2025-57349 exploitable, and should I be worried?

Whether CVE-2025-57349 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-2025-57349 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-2025-57349 in messageformat

Q: Which versions of messageformat are affected by CVE-2025-57349?

messageformat (npm) versions < 2.3.0 is affected.

Q: Is there a fix for CVE-2025-57349?

Yes. CVE-2025-57349 is fixed in 3.0.0-beta.0. Upgrade to this version or later.

Q: Is CVE-2025-57349 exploitable, and should I be worried?

Whether CVE-2025-57349 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-2025-57349 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-2025-57349?

Upgrade messageformat to 3.0.0-beta.0 or later.

Summary

messageformat has a prototype pollution vulnerability

The messageformat package, an implementation of the Unicode MessageFormat 2 specification for JavaScript, is vulnerable to prototype pollution due to improper handling of message key paths in versions prior to 2.3.0. The flaw arises when processing nested message keys containing special characters (e.g., proto ), which can lead to unintended modification of the JavaScript Object prototype. This vulnerability may allow a remote attacker to inject properties into the global object prototype via specially crafted message input, potentially causing denial of service or other undefined behaviors in applications using the affected component.

Impact

Affected versions

messageformat (< 2.3.0)

Security releases

messageformat → 3.0.0-beta.0 (npm)

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 messageformat to 3.0.0-beta.0 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-2025-57349? CVE-2025-57349 is a low-severity security vulnerability in messageformat (npm), affecting versions < 2.3.0. It is fixed in 3.0.0-beta.0.
Which versions of messageformat are affected by CVE-2025-57349? messageformat (npm) versions < 2.3.0 is affected.
Is there a fix for CVE-2025-57349? Yes. CVE-2025-57349 is fixed in 3.0.0-beta.0. Upgrade to this version or later.
Is CVE-2025-57349 exploitable, and should I be worried? Whether CVE-2025-57349 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-2025-57349 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-2025-57349? Upgrade messageformat to 3.0.0-beta.0 or later.