CVE-2026-53517Network attack vector

Persistent OAuth access via refresh-token rotation race

Published Jul 15, 2026 · Updated Jul 15, 2026

Race condition in Better Auth OAuth Provider allows remote authenticated users to retain OAuth access by replaying a stolen refresh token. The token endpoint reads the oauthRefreshToken row and later revokes it with an id-only update, so concurrent requests pass the same revoked check. Exposure requires offline_access refresh-token issuance and concurrent redemption of one token; a stolen token sustains access at the user's scope.

CVSS severity8.1
High
EPSS probability0.42%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Race condition in Better Auth OAuth Provider allows remote authenticated users to retain OAuth access by replaying a stolen refresh token. The token endpoint reads the oauthRefreshToken row and later revokes it with an id-only update, so concurrent requests pass the same revoked check. Exposure requires offline_access refresh-token issuance and concurrent redemption of one token; a stolen token sustains access at the user's scope.

The record

CVE
CVE-2026-53517
Published
Jul 15, 2026
Updated
Jul 15, 2026
Vendor
Better Auth
Product
Better Auth OAuth Provider Plugin
Classifications
CWE-294, CWE-367, CWE-613, CWE-362, T1550.001
Attack vector
network
Privileges
authenticated

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

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=>= 1.6.0, < 1.6.11

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Better Auth · Better Auth OAuth Provider Pluginversion=>= 1.6.0, < 1.6.11
Better Auth · Better Authversion=>= 1.4.8-beta.7, < 1.6.0

Published CVSS scores

8.1GitHubCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A: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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-294Authentication Bypass by Capture-replay
CWE-367Time-of-check Time-of-use (TOCTOU) Race Condition
CWE-613Insufficient Session Expiration
CWE-362Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
T1550.001Application Access Token

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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