What is CVE-2026-9675?

CVE-2026-9675 is a high-severity vulnerability in Undici, classified under Uncontrolled Resource Consumption. CVSS score: 7.5/10. Published 2026-06-17.

How severe is CVE-2026-9675?

High severity. CVSS v3 base score is 7.5 out of 10.

Resource exhaustion in Undici

CVE-2026-9675

Impact: The undici WebSocket client enforces maxPayloadSize per-frame but does not enforce the cumulative size of fragmented uncompressed messages. A malicious WebSocket server can stream many small fragments that each pass per-frame valid…

Vulnerability class: DoS (Denial of Service)

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Undici — versions 8.0.0, 8.5.0

Weakness classification (CWE)

CWE-400 — Uncontrolled Resource Consumption
CWE-770 — Allocation of Resources Without Limits or Throttling

References

ce714d77-add3-4f53-aff5-83d477b104bb
ce714d77-add3-4f53-aff5-83d477b104bb

Frequently asked questions

What is CVE-2026-9675?: CVE-2026-9675 is a high-severity vulnerability in Undici, classified under Uncontrolled Resource Consumption. CVSS score: 7.5/10. Published 2026-06-17.
How severe is CVE-2026-9675?: High severity. CVSS v3 base score is 7.5 out of 10.