CVE-2026-29199

phpBB before 3.3.16 is vulnerable to Host Header Injection that can lead to password rest link poisoning. When force_server_vars is disabled, the servers hostname may be extracted from the HTTP Host header which is used to generate the password reset link URL. An attacker who can manipulate the Host header (e.g. through misconfigured host setup or missing header validation by the webserver) can cause password reset emails to contain a link pointing to an attacker-controlled domain, potentially leading to account takeover.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://hackerone.com/reports/3543246	Permissions Required

Configurations

Configuration 1 (hide)

cpe:2.3:a:phpbb:phpbb:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-05-04 07:15

Updated : 2026-06-17 10:29

NVD link : CVE-2026-29199

Mitre link : CVE-2026-29199

CVE.ORG link : CVE-2026-29199

JSON object : View

Products Affected

phpbb

phpbb

CWE

CWE-640

Weak Password Recovery Mechanism for Forgotten Password

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