CVE-2026-25923

my little forum is a PHP and MySQL based internet forum that displays the messages in classical threaded view. Prior to 20260208.1, the application fails to filter the phar:// protocol in URL validation, allowing attackers to upload a malicious Phar Polyglot file (disguised as JPEG) via the image upload feature, trigger Phar deserialization through BBCode [img] tag processing, and exploit Smarty 4.1.0 POP chain to achieve arbitrary file deletion. This vulnerability is fixed in 20260208.1.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/My-Little-Forum/mylittleforum/releases/tag/20260208.1	Product Release Notes
https://github.com/My-Little-Forum/mylittleforum/security/advisories/GHSA-wr9p-3c3g-78fw	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:mylittleforum:my_little_forum:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-02-09 22:16

Updated : 2026-03-17 20:30

NVD link : CVE-2026-25923

Mitre link : CVE-2026-25923

CVE.ORG link : CVE-2026-25923

JSON object : View

Products Affected

mylittleforum

my_little_forum

CWE

CWE-434

Unrestricted Upload of File with Dangerous Type

CWE-502

Deserialization of Untrusted Data

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