What is CVE-2026-22036?

CVE-2026-22036 is a medium-severity vulnerability in Node.js Undici, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 5.9/10. Published 2026-01-14.

How severe is CVE-2026-22036?

Medium severity. CVSS v3 base score is 5.9 out of 10.

Resource exhaustion in Node.js Undici

CVE-2026-22036

Undici is an HTTP/1.1 client for Node.js. Prior to 7.18.0 and 6.23.0, the number of links in the decompression chain is unbounded and the default maxHeaderSize allows a malicious server to insert thousands compression steps leading to high CPU usage and excessive memory allocation. This vulnerability is fixed in 7.18.0 and 6.23.0.

EPSS: 0.004 (35.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Nodejs Undici — versions < 6.23.0, >= 7.0.0, < 7.18.2

Weakness classification (CWE)

CWE-770 — Allocation of Resources Without Limits or Throttling

References

security-advisories@github.com (x_refsource_CONFIRM, Vendor Advisory)
security-advisories@github.com (Patch, x_refsource_MISC)

Frequently asked questions

What is CVE-2026-22036?: CVE-2026-22036 is a medium-severity vulnerability in Node.js Undici, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 5.9/10. Published 2026-01-14.
How severe is CVE-2026-22036?: Medium severity. CVSS v3 base score is 5.9 out of 10.