Cyber Posture

CVE-2026-38526

Critical

Published: 14 April 2026

Published
14 April 2026
Modified
17 April 2026
KEV Added
Patch
CVSS Score 9.9 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
EPSS Score 0.0006 19.1th percentile
Risk Priority 20 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-38526 is a critical-severity Unrestricted Upload of File with Dangerous Type (CWE-434) vulnerability. Its CVSS base score is 9.9 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 19.1th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-2 (Flaw Remediation).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190) and 2 other techniques. What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

prevent

Directly prevents arbitrary file uploads by validating file types and content at the /admin/tinymce/upload endpoint to block crafted PHP files.

prevent

Restricts the upload endpoint to only safe file types, excluding dangerous PHP files and mitigating CWE-434 unrestricted uploads.

prevent

Remediates the specific flaw in Webkul Krayin CRM v2.2.x upload endpoint through timely patching to eliminate the arbitrary code execution vulnerability.

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1100 Web Shell Persistence
A Web shell is a Web script that is placed on an openly accessible Web server to allow an adversary to use the Web server as a gateway into a network.
T1505.003 Web Shell Persistence
Adversaries may backdoor web servers with web shells to establish persistent access to systems.
Why these techniques?

The authenticated arbitrary PHP file upload vulnerability in a public-facing web app directly enables exploitation of the application for initial access (T1190) and facilitates web shell installation for code execution (T1100, T1505.003).

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

NVD Description

An authenticated arbitrary file upload vulnerability in the /admin/tinymce/upload endpoint of Webkul Krayin CRM v2.2.x allows attackers to execute arbitrary code via uploading a crafted PHP file.

Deeper analysisAI

CVE-2026-38526 is an authenticated arbitrary file upload vulnerability in the /admin/tinymce/upload endpoint of Webkul Krayin CRM v2.2.x. This issue, linked to CWE-434 (Unrestricted Upload of File with Dangerous Type), allows attackers to upload crafted PHP files, resulting in arbitrary code execution. Published on 2026-04-14, it carries a CVSS v3.1 base score of 9.9 (AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H), marking it as critically severe.

An authenticated attacker with low privileges can exploit this vulnerability remotely over the network with low complexity and no user interaction required. By uploading a malicious PHP file through the affected endpoint, the attacker achieves arbitrary code execution, leading to high-impact compromise of confidentiality, integrity, and availability, with a changed scope that amplifies the effects across the system.

Advisories and a proof-of-concept exploit are documented in the GitHub repository https://github.com/TREXNEGRO/Security-Advisories/tree/main/CVE-2026-38526, with the POC details at https://github.com/TREXNEGRO/Security-Advisories/blob/main/CVE-2026-38526/poc.md. The project's repository is available at https://github.com/krayin/laravel-crm.

Details

CWE(s)

CVEs Like This One

CVE-2025-67924Shared CWE-434
CVE-2025-62056Shared CWE-434
CVE-2025-6057Shared CWE-434
CVE-2026-27067Shared CWE-434
CVE-2020-36942Shared CWE-434
CVE-2024-57169Shared CWE-434
CVE-2023-53933Shared CWE-434
CVE-2025-68909Shared CWE-434
CVE-2021-47757Shared CWE-434
CVE-2025-68986Shared CWE-434

References