Better Auth URL parameter HTML Injection (Reflected Cross-Site scripting)
Key facts
- Attack vector
- —
- Privileges required
- —
- User interaction
- —
- Attack complexity
- —
- Impact type
- Cross-site scripting
- Confidentiality · integrity · availability
- —
- Fix status
- Fixed
No CVSS vector from any source. Fix status from GitHub. Impact type from CWE-79.
Summary
### 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.
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | better-auth (npm) | 0.0.2 to before 1.1.16 | 1.1.16 | Patch available | GHSA-9x4v-xfq5-m8x5 |
- better-auth (npm) Vendor— Affected 0.0.2 to before 1.1.16 Fixed in 1.1.16 Patch available GHSA-9x4v-xfq5-m8x5
Remediation
- Fix · GHSA-9x4v-xfq5-m8x5 better-auth (npm) Fixed in 1.1.16 Advisory →
Timeline
- 2026-10-03 Threatist record created from GHSA-9x4v-xfq5-m8x5
References
Other 4
- https://github.com/better-auth/better-auth/security/advisories/GHSA-9x4v-xfq5-m8x5
- https://github.com/better-auth/better-auth/commit/7ae340e2eddad641b7e43d24d37c58a66ce9ddcf
- https://github.com/better-auth/better-auth
- https://github.com/better-auth/better-auth/blob/05ada0b79dbcac93cc04ceb79b23ca598d07830c/packages/better-auth/src/api/routes/error.ts#L81
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences