CVE-2025-61928Public exploitNetwork attack vector

Unauthenticated account takeover via attacker-selected user ID

Published Oct 9, 2025 · Updated Oct 9, 2025

Authentication bypass in Better Auth before 1.3.26 allows remote attackers to create API keys for arbitrary users via the API-key plugin. The create and update handlers treat a request-body userId as the current user when no session exists, then skip server-only field validation. Exposure requires the API-key plugin route to be mounted; a created key grants the targeted user's authenticated privileges.

CVSS severity9.3
Critical
EPSS probability17.93%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authentication bypass in Better Auth before 1.3.26 allows remote attackers to create API keys for arbitrary users via the API-key plugin. The create and update handlers treat a request-body userId as the current user when no session exists, then skip server-only field validation. Exposure requires the API-key plugin route to be mounted; a created key grants the targeted user's authenticated privileges.

The record

CVE
CVE-2025-61928
Published
Oct 9, 2025
Updated
Oct 9, 2025
Vendor
Better Auth
Product
Better Auth
Classifications
CWE-306, CWE-285, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 9, 2025CVE publishedPublication date reported by the CVE source.
  2. Oct 9, 2025Record 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=< 1.3.26

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Better Auth · Better Authversion=< 1.3.26

Published CVSS scores

9.3GitHub, Inc.CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
8.6GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L

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 exploitPublished

Weakness, pattern, technique

CWE-306Missing Authentication for Critical Function
CWE-285Improper Authorization
T1190Exploit Public-Facing Application

Public exploit references

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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