GHSA-9x4v-xfq5-m8x5

Better Auth URL parameter HTML Injection (Reflected Cross-Site scripting)

Description

### Summary The better-auth `/api/auth/error` page was vulnerable to HTML injection, resulting in a reflected cross-site scripting (XSS) vulnerability. ### Details The value of `error` URL parameter was reflected as HTML on the error page: https://github.com/better-auth/better-auth/blob/05ada0b79dbcac93cc04ceb79b23ca598d07830c/packages/better-auth/src/api/routes/error.ts#L81 ### Impact An attacker who exploited this vulnerability by coercing a user to visit a specially-crafted URL could execute arbitrary JavaScript in the context of the user's browser.

Affected packages

References

• https://github.com/better-auth/better-auth/security/advisories/GHSA-9x4v-xfq5-m8x5 WEB
• https://github.com/better-auth/better-auth/commit/7ae340e2eddad641b7e43d24d37c58a66ce9ddcf WEB
• https://github.com/better-auth/better-auth PACKAGE
• https://github.com/better-auth/better-auth/blob/05ada0b79dbcac93cc04ceb79b23ca598d07830c/packages/better-auth/src/api/routes/error.ts#L81 WEB

Sources