CVE-2026-100523

Cotonti through 1.0.0 contains an open redirect vulnerability in message.php that base64-decodes the redirect parameter without domain validation. Unauthenticated attackers can craft malicious links with encoded external URLs to redirect users to arbitrary sites via meta refresh tags for phishing attacks.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/Cotonti/Cotonti
https://github.com/Cotonti/Cotonti/blob/1.0.0/message.php
https://github.com/Cotonti/Cotonti/blob/1.0.0/system/common.php
https://github.com/Cotonti/Cotonti/issues/1907
https://github.com/Cotonti/Cotonti/pull/1908
https://www.vulncheck.com/advisories/cotonti-through-1.0.0-open-redirect-via-message-php-redirect-parameter

Configurations

No configuration.

History

26 Sep 2026, 01:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-26 01:17

Updated : 2026-10-05 15:17

NVD link : CVE-2026-100523

Mitre link : CVE-2026-100523

CVE.ORG link : CVE-2026-100523

JSON object : View

Products Affected

No product.

CWE

CWE-601

URL Redirection to Untrusted Site ('Open Redirect')

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