CVE-2026-45364 Better Auth: Rate limiter keys IPv6 addresses individually and is bypassable via prefix rotation

Better Auth is an authentication and authorization library for TypeScript. Prior to 1.4.17 and 1.5.0-beta.9, Better Auth's HTTP rate limiter keyed each request by the exact textual IP address it received in x-forwarded-for or the configured IP-bearing header. IPv6 clients controlling a typical /6...

Better Auth: Rate limiter keys IPv6 addresses individually and is bypassable via prefix rotation

Am I affected? Users are affected if all of the following are true: - Their app uses better-auth at a version 1.4.17, or at a v1.5 prerelease tagged = 1.5.0-beta.8. - The apps authentication endpoints serve clients reachable over IPv6. Most managed hosts including Cloudflare, Vercel, Fly.io, AWS...

NPM: Better Auth: Rate limiter keys IPv6 addresses individually and is bypassable via prefix rotation

NPM: Better Auth: Rate limiter keys IPv6 addresses individually and is bypassable via prefix rotation vulnerability discovered by ? in WordPress Npm better-auth versions 1.4.17...

GHSA-P6V2-XCPG-H6XW Better Auth: Rate limiter keys IPv6 addresses individually and is bypassable via prefix rotation

Am I affected? Users are affected if all of the following are true: - Their app uses better-auth at a version 1.4.17, or at a v1.5 prerelease tagged = 1.5.0-beta.8. - The apps authentication endpoints serve clients reachable over IPv6. Most managed hosts including Cloudflare, Vercel, Fly.io, AWS...