Reflected Cross-Site Scripting Vulnerability in phpBB Registration Module
CVE-2026-87901

8.3HIGH

Key Information:

Vendor

PHPbb

Status
PHPbb
Vendor
CVE Published:
23 October 2026

What is CVE-2026-87901?

The phpBB registration module contains an improper sanitization vulnerability that allows for reflected Cross-Site Scripting (XSS) attacks. By exploiting this weakness, an attacker can craft a malicious link that, when visited, executes arbitrary JavaScript in the context of the affected user's browser. This could lead to theft of sensitive information, session hijacking, or redirecting users to malicious sites.

Affected Version(s)

phpBB 3.3.0 <= 3.3.18

References

https://www.phpbb.com/community/viewtopic.php?t=2675305

CVSS V3.0

Score:
8.3
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
Required
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Aikido Security (aikido_security)
.