CVE-2026-53512Network attack vector

OAuth token minting via omitted client-secret verification

Published Jul 15, 2026 · Updated Jul 15, 2026

Improper authentication in Better Auth before 1.6.11 allows remote attackers to mint OAuth tokens through legacy plugin token endpoints. The oidcProvider and mcp refresh paths accept a bound refreshToken row and matching client_id without verifying a confidential client's client_secret. Exploitation requires an enabled legacy plugin, a registered confidential client, and a valid refresh token; minted tokens retain the original user's scope until revocation.

CVSS severity9.1
Critical
EPSS probability0.27%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authentication in Better Auth before 1.6.11 allows remote attackers to mint OAuth tokens through legacy plugin token endpoints. The oidcProvider and mcp refresh paths accept a bound refreshToken row and matching client_id without verifying a confidential client's client_secret. Exploitation requires an enabled legacy plugin, a registered confidential client, and a valid refresh token; minted tokens retain the original user's scope until revocation.

The record

CVE
CVE-2026-53512
Published
Jul 15, 2026
Updated
Jul 15, 2026
Vendor
Better Auth
Product
Better Auth
Classifications
CWE-345, CWE-287, CWE-863, CWE-306, T1528
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 15, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 15, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 1.6.11

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Better Auth · Better Authversion=< 1.6.11

Published CVSS scores

9.1NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
9.1GitHub, Inc.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

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-345Insufficient Verification of Data Authenticity
CWE-287Improper Authentication
CWE-863Incorrect Authorization
CWE-306Missing Authentication for Critical Function
T1528Steal Application Access Token

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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