CVE-2026-108740

GoatCounter through 2.7.0 contains a mass assignment privilege escalation vulnerability in the userPrefSave handler that allows logged-in users to modify protected account fields via form-encoded requests. Attackers with read-only access can POST user.access[all]=* and user.email_verified=true to /user/pref, bypassing readonly tags to gain superuser or admin access.

CVSS v3 8.3 HIGH

8.3^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/arp242/goatcounter
https://github.com/arp242/goatcounter/blob/7e91d8a9bdbb0dd48496e498c5680f8f3477a1b4/handlers/settings_user.go#L33-L99
https://github.com/arp242/goatcounter/blob/7e91d8a9bdbb0dd48496e498c5680f8f3477a1b4/user.go#L191-L218
https://hackmd.io/@haind03/goatcounter-user-pref-access-mass-assignment-20261011
https://www.vulncheck.com/advisories/goatcounter-through-2.7.0-privilege-escalation-via-user-pref-mass-assignment

Configurations

No configuration.

History

11 Oct 2026, 13:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-11 13:17

Updated : 2026-10-16 19:18

NVD link : CVE-2026-108740

Mitre link : CVE-2026-108740

CVE.ORG link : CVE-2026-108740

JSON object : View

Products Affected

No product.

CWE

CWE-915

Improperly Controlled Modification of Dynamically-Determined Object Attributes

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