CVE-2020-15168

The size option isn't honored after following a redirect in node-fetch

Workarounds

None, it is strongly recommended to update as soon as possible.

For more information

If you have any questions or comments about this advisory:

• Open an issue in node-fetch
• Contact one of the core maintainers.

Node Fetch did not honor the size option after following a redirect, which means that when a content size was over the limit, a FetchError would never get thrown and the process would end without failure.

For most people, this fix will have a little or no impact. However, if you are relying on node-fetch to gate files above a size, the impact could be significant, for example: If you don't double-check the size of the data after fetch() has completed, your JS thread could get tied up doing work on a large file (DoS) and/or cost you money in computing.

The application does not adequately validate input before processing it, allowing unexpected values to reach sensitive code paths. Typical impact: varies by context: data corruption, logic bypass, or denial of service.

CVE-2020-15168 has a CVSS score of 2.6 (Low). The vector is network-reachable, low privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (3.0.0-beta.9, 2.6.1); upgrading removes the vulnerable code path.

Kodem intelligence

Already deployed Kodem?

We released patched versions for both stable and beta channels:

• For v2: 2.6.1
• For v3: 3.0.0-beta.9

1. What is CVE-2020-15168? CVE-2020-15168 is a low-severity improper input validation vulnerability in node-fetch (npm), affecting versions >= 3.0.0-beta.1, <= 3.0.0-beta.8. It is fixed in 3.0.0-beta.9, 2.6.1. The application does not adequately validate input before processing it, allowing unexpected values to reach sensitive code paths.
2. How severe is CVE-2020-15168? CVE-2020-15168 has a CVSS score of 2.6 (Low). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of node-fetch are affected by CVE-2020-15168? node-fetch (npm) versions >= 3.0.0-beta.1, <= 3.0.0-beta.8 is affected.
4. Is there a fix for CVE-2020-15168? Yes. CVE-2020-15168 is fixed in 3.0.0-beta.9, 2.6.1. Upgrade to this version or later.
5. Is CVE-2020-15168 exploitable, and should I be worried? Whether CVE-2020-15168 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
6. What actually determines whether CVE-2020-15168 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.
7. How do I fix CVE-2020-15168?
   • Upgrade node-fetch to 3.0.0-beta.9 or later
   • Upgrade node-fetch to 2.6.1 or later

Other vulnerabilities in node-fetch