CVE-2026-67333
better-auth before 1.6.13 Stored XSS via javascript redirect_uri
- Published
- Updated
- Reserved
- Assigned by
- VulnCheck
Description
better-auth before 1.6.13 (and pre-release builds 1.7.0-beta.0 through 1.7.0-beta.3) fail to validate the scheme of redirect_uris registered via the deprecated oidc-provider plugin and the mcp plugin (which wraps the same provider). An attacker can register an OAuth client with a javascript: redirect_uri, which the authorization server later returns unchanged in the consent response. If the deployment's consent page navigates the browser to the returned redirectURI (e.g. assigning it to window.location.href), the attacker's JavaScript executes in the authorization-server origin, exposing the victim's session and enabling account takeover.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| VulnCheckCNA (assigner) | 4.0 | Medium5.1 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N |
| VulnCheckCNA (assigner) | 3.1 | High7.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N |
| NVDNVD · Deferred | 4.0 | Medium5.1 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
- EPSS (exploitation in 30 days)
- 0.26% · top 82% of all CVEs (6 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.1.
Weakness
Affected products
- affected < 1.6.13
- unaffected 1.6.13
- affected 1.7.0-beta.0 – < 1.7.0-beta.4
- unaffected 1.7.0-beta.4
References (2)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-67333)Record last updated .