CVE-2026-48611 PUBLISHED

Assigner: hackerone
Reserved: 22.05.2026 Published: 12.06.2026 Updated: 12.06.2026

Improper authentication checks in the OAuth implementation allow account hijacking even when OAuth is not configured or enabled leading to unauthorized access in default installations.

Metrics

CVSS 3.0

CVSS Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS Score: 9.8

Attack Vector	Network	Scope	Unchanged
Attack Complexity	Low	Confidentiality Impact	High
Privileges Required	None	Integrity Impact	High
User Interaction	None	Availability Impact	High

CVSS 3.0

Product Status

Vendor	phpBB
Product	phpBB
Versions	Default: unaffected affected from 3.3.0 to 3.3.16 (incl.)

References

https://www.phpbb.com/community/viewtopic.php?t=2672170

Problem Types

CWE-287 Improper Authentication - Generic CWE