Quick answer
Direct answer
Risk scores
| CVSS metric | What it means |
|---|---|
| Attack vector (AV:N) | Network: reachable remotely |
| Attack complexity (AC:L) | Low complexity |
| Attack requirements (AT:P) | Attack requirements present |
| Privileges required (PR:N) | No privileges required |
| User interaction (UI:N) | No user interaction |
| Confidentiality (VC:H) | High confidentiality impact |
| Integrity (VI:H) | High integrity impact |
| Availability (VA:N) | No availability impact |
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/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
About Better-Auth Better Auth
CVE-2026-53512 affects Better-Auth Better Auth, a product from Better-Auth. Before acting, confirm where Better-Auth Better Auth runs in your estate, who owns it and whether it is reachable from the internet, because exposure decides real risk more than the score alone.
What the flaw is
In plain terms: Better Auth is an authentication and authorization library for TypeScript. Prior to 1.6.11, the legacy oidcProvider and mcp plugins expose OAuth token endpoints whose refresh_token grant authenticates only possession of the bound refreshToken row and matching client_id, without verifying the confidential client's client_secret, allowing an attacker with a valid refresh_token to mint access tokens and rotated refresh tokens through /api/auth/oauth2/token or /api/auth/mcp/token. The @better-auth/oauth-provider package is not affected. This issue is fixed in version 1.6.11.
The weakness class is Improper Authentication. The software does not properly prove who a user is.
Based on its CVSS vector, the flaw can be reached over the network, needs no login, and needs no user interaction. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.
Affected versions and timeline
| Field | Detail |
|---|---|
| Product | Better-Auth Better Auth |
| Affected versions | Better Auth before 1.6.11 |
| Published | Jul 15, 2026 |
| Last modified | Jul 21, 2026 |
| Added to CISA KEV | Not listed |
| Assigning CNA | security-advisories@github.com |
How to detect it
- Inventory every instance of Better-Auth Better Auth and record the running version against the affected range above.
- Check external attack surface scans for internet facing instances of the component.
- Review logs on affected systems for unusual requests, errors or new processes around the vulnerable function.
- Confirm with an authenticated vulnerability scan once your scanner has a check for this CVE.
How to fix it
- Apply the fixed version of Better-Auth Better Auth named in the vendor advisory.
- If patching must wait, restrict network access to the affected service and put it behind authentication or a web application firewall rule.
- Rescan after the change to prove the exposure is gone, then close the ticket.
CTEM action plan
| CTEM stage | What to do for this CVE |
|---|---|
| Scope | Add every business service that depends on Better-Auth Better Auth to the current CTEM cycle. |
| Discover | Find all instances, including shadow and cloud deployments, and record versions and exposure. |
| Prioritize | Rank using EPSS and CVSS together with asset exposure and business impact. |
| Validate | Confirm the flaw is reachable and exploitable in your environment and that compensating controls work. |
| Mobilize | Assign the fix to the asset owner with a due date matched to the priority, then verify closure. |
CWE References
- CWE-287: Improper Authentication More CVEs with this weakness
- CWE-306: Missing Authentication More CVEs with this weakness
- CWE-345 More CVEs with this weakness
- CWE-863: Incorrect Authorization More CVEs with this weakness
Technical References
Frequently asked questions
Related CVEs
Better Auth is an authentication and authorization library for TypeScript. From 1.6.0 until 1.6.11, the @better-auth/oauth-provider POST /oauth2/token endpoint for the authorization_code grant redeems a single-use authorization code through a non-atomic find-then-delete sequence, allowing two concurrent requests to pass the read step and mint independent access tokens, refresh tokens, and ID tokens; legacy /oauth2/token and /mcp/token paths in oidc-provider and mcp plugins share the same primitive. This issue is fixed in version 1.6.11.
A remote authentication bypass vulnerability exists in HPE AutoPass License Server (APLS).
Improper authentication in Azure Key Vault allows an unauthorized attacker to elevate privileges over a network.
Dokans Multi-Tenancy Based eCommerce Platform SaaS 3.9.2 allows unauthenticated remote attackers to obtain sensitive application configuration data via direct request to /script/.env file. The exposed file contains Laravel application encryption key (APP_KEY), database credentials, SMTP/SendGrid API credentials, and internal configuration parameters, enabling complete system compromise including authentication bypass via session token forgery, direct database access to all tenant data, and email infrastructure takeover. Due to the multi-tenancy architecture, this vulnerability affects all tenants in the system.
FUXA is a web-based Process Visualization (SCADA/HMI/Dashboard) software. Prior to 1.2.10, an authentication bypass vulnerability in FUXA allows an unauthenticated, remote attacker to gain administrative access via the heartbeat refresh API and execute arbitrary code on the server. This issue has been patched in FUXA version 1.2.10.
The vulnerability exists in BLUVOYIX due to improper authentication in the BLUVOYIX backend APIs. An unauthenticated remote attacker could exploit this vulnerability by sending specially crafted HTTP requests to the vulnerable APIs. Successful exploitation of this vulnerability could allow the attacker to gain full access to customers' data and completely compromise the targeted platform.
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