Is this vulnerability remotely exploitable, and how broad is the impact?

Yes. If the forum allows remote users to upload images and render them via `[img]` tags, an attacker can exploit the issue over the network. The primary direct impact is arbitrary file deletion within the permissions of the web server user, which can in turn lead to denial of service or facilitate secondary attacks.

What level of access does an attacker need to exploit this?

The attacker generally needs the ability to upload images and cause them to be rendered or processed by the forum—often available to standard registered users depending on configuration. They do not need shell access or administrative privileges; exploitation occurs via crafted HTTP requests and regular forum features.

What is the safest general fix pattern for developers?

Combine strict upload validation with protocol and wrapper restrictions, ensure untrusted files are stored and served from isolated locations, and remove or harden any code paths that touch `phar://` or deserialize untrusted data. Additionally, review the templating engine configuration to eliminate dangerous gadget chains that can perform filesystem operations.

Severity:

CRITICAL RISK

(9.1)

Unrestricted File Upload & PHP Phar Deserialization (CWE-434, CWE-502) in my little forum Image Handling

CVE-2026-25923

Published:

Feb 9, 2026

Status:

Analyzed

Summary

Affected Context

Exploit Preconditions

Why This Happens

Potential Impact

General Mitigation Guidance

How Teams Detect Issues Like This

Frequently Asked Questions

Source

NDV

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May 6, 2026

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HIGH RISK

HIGH

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Authorization Bypass (CWE-863) in OpenClaw Matrix Room Control Commands

Privilege Escalation via Bypassed Access Control

May 6, 2026

Vulnerability Type

Category:

Unrestricted File Upload and Unsafe Deserialization

CWE:

CWE-434;CWE-502

Impact:

Arbitrary File Deletion and Server-Side Data Integrity Compromise

Severity:

CRITICAL RISK

(9.1)

CVSS Version:

3.1

Vulnerability Type

Category:

Unrestricted File Upload and Unsafe Deserialization

CWE:

CWE-434;CWE-502

Impact:

Arbitrary File Deletion and Server-Side Data Integrity Compromise

Severity:

CRITICAL RISK

(9.1)

CVSS Version:

3.1

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Unrestricted File Upload & PHP Phar Deserialization (CWE-434, CWE-502) in my little forum Image Handling

Summary

Affected Context

Exploit Preconditions

Why This Happens

Potential Impact

General Mitigation Guidance

How Teams Detect Issues Like This

Frequently Asked Questions

Source

Recent Vulnerabilities

HIGH RISK

HIGH

(8.6)

Server-Side Request Forgery (CWE-918) in OpenClaw Zalo Plugin sendPhoto

HIGH RISK

HIGH

(8.8)

Authorization Bypass (CWE-863) in OpenClaw Matrix Room Control Commands

Vulnerability Type

Vulnerability Type

Vulnerability Type

Catch This CVE While Code Is Being Written

Ship clean & secure code faster

Ship clean & secure code faster

Ship clean & secure code faster

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