What is CVE-2026-15144?

CVE-2026-15144 is a high-severity vulnerability in @Fastify/rate-limit, classified under Improper Restriction of Excessive Authentication Attempts. CVSS score: 7.3/10. Published 2026-07-29.

How severe is CVE-2026-15144?

High severity. CVSS v3 base score is 7.3 out of 10.

Resource exhaustion in @Fastify/rate-limit

CVE-2026-15144

@fastify/rate-limit before 11.2.0 keys rate-limit buckets by the verbatim client IP string returned from request.ip. Because a single IPv6 client can control a large address range (a /64 holds 2^64 distinct addresses) and the same address…

CVSS v3 metric

CVSS v3 base score 7.3 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L.

Affected products

@Fastify/rate-limit — versions 0, 11.2.0

Weakness classification (CWE)

CWE-307 — Improper Restriction of Excessive Authentication Attempts
CWE-770 — Allocation of Resources Without Limits or Throttling

References

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ce714d77-add3-4f53-aff5-83d477b104bb

Frequently asked questions

What is CVE-2026-15144?: CVE-2026-15144 is a high-severity vulnerability in @Fastify/rate-limit, classified under Improper Restriction of Excessive Authentication Attempts. CVSS score: 7.3/10. Published 2026-07-29.
How severe is CVE-2026-15144?: High severity. CVSS v3 base score is 7.3 out of 10.