{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-15144","assignerOrgId":"ce714d77-add3-4f53-aff5-83d477b104bb","state":"PUBLISHED","assignerShortName":"openjs","dateReserved":"2026-07-08T17:27:38.479Z","datePublished":"2026-07-29T16:10:24.560Z","dateUpdated":"2026-07-29T17:56:31.392Z"},"containers":{"cna":{"providerMetadata":{"orgId":"ce714d77-add3-4f53-aff5-83d477b104bb","shortName":"openjs","dateUpdated":"2026-07-29T16:10:24.560Z"},"descriptions":[{"lang":"en","value":"@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 has multiple valid textual representations, an IPv6 capable client can defeat the rate-limit boundary by rotating addresses or by rewriting the same address in different forms. Applications that use @fastify/rate-limit to protect endpoints such as authentication, password reset, OTP delivery, or expensive API calls can be bypassed by IPv6 clients behind a proxy that surfaces IPv6 to the origin when trustProxy is enabled. The issue is fixed in @fastify/rate-limit 11.2.0, where the default key generator normalizes IPv6 addresses to their canonical form, collapses IPv4 mapped IPv6 to IPv4, and applies a configurable prefix mask (default /64) via a new ipv6Subnet option.","supportingMedia":[{"type":"text/html","base64":false,"value":"@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 has multiple valid textual representations, an IPv6 capable client can defeat the rate-limit boundary by rotating addresses or by rewriting the same address in different forms. Applications that use @fastify/rate-limit to protect endpoints such as authentication, password reset, OTP delivery, or expensive API calls can be bypassed by IPv6 clients behind a proxy that surfaces IPv6 to the origin when trustProxy is enabled. The issue is fixed in @fastify/rate-limit 11.2.0, where the default key generator normalizes IPv6 addresses to their canonical form, collapses IPv4 mapped IPv6 to IPv4, and applies a configurable prefix mask (default /64) via a new ipv6Subnet option."}]}],"affected":[{"vendor":"@fastify/rate-limit","product":"@fastify/rate-limit","defaultStatus":"unaffected","versions":[{"versionType":"semver","status":"affected","version":"0","lessThan":"11.2.0"},{"versionType":"semver","status":"unaffected","version":"11.2.0"}],"packageURL":"pkg:npm/@fastify/rate-limit"}],"references":[{"url":"https://github.com/fastify/fastify-rate-limit/security/advisories/GHSA-grpc-p53c-r64v"},{"url":"https://cna.openjsf.org/security-advisories.html"}],"credits":[{"lang":"en","type":"reporter","value":"0xShemesh"},{"lang":"en","type":"remediation developer","value":"mcollina"},{"lang":"en","type":"remediation reviewer","value":"climba03003"},{"lang":"en","type":"remediation reviewer","value":"UlisesGascon"}],"title":"@fastify/rate-limit vulnerable to rate-limit bypass via IPv6 address rotation","metrics":[{"format":"CVSS","cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L","baseScore":7.3,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-307","lang":"en","description":"CWE-307: Improper Restriction of Excessive Authentication Attempts","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-770","lang":"en","description":"CWE-770: Allocation of Resources Without Limits or Throttling","type":"CWE"}]}],"x_generator":{"engine":"cve-kit 1.0.0"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-07-29T17:56:23.752502Z","id":"CVE-2026-15144","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-07-29T17:56:31.392Z"}}]}}