CVE-2026-29859

CriticalPublic PoC

Published: 18 March 2026

Published

18 March 2026

Modified

23 March 2026

KEV Added

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Patch

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CVSS Score 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Score 0.0014 33.7th percentile

Risk Priority 20 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-29859 is a critical-severity Cross-site Scripting (CWE-79) vulnerability in Aapanel Aapanel. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 33.7th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

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). What defenders deploy: see the NIST 800-53 controls recommended below.

Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

SI-10 Information Input Validation good match

prevent

Directly validates uploaded files to reject crafted malicious inputs, preventing arbitrary file uploads that lead to code execution in aaPanel.

SI-2 Flaw Remediation good match

prevent

Remediates the specific arbitrary file upload flaw in aaPanel v7.57.0 by applying vendor patches from the GitHub repository.

SI-3 Malicious Code Protection good match

preventdetect

Scans uploaded files for malicious code at entry points, blocking or eradicating crafted executables before they can be executed.

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.

attack.mitre.org →

Why these techniques?

Arbitrary file upload vulnerability in public-facing web application (aaPanel) enables remote unauthenticated code execution, directly facilitating T1190: Exploit Public-Facing Application.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

NVD Description

An arbitrary file upload vulnerability in aaPanel v7.57.0 allows attackers to execute arbitrary code via uploading a crafted file.

Deeper analysisAI

CVE-2026-29859 is an arbitrary file upload vulnerability in aaPanel version 7.57.0 that enables attackers to execute arbitrary code by uploading a crafted file. Published on 2026-03-18T18:16:27.347, it carries a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H) and maps to CWE-79 and CWE-434.

The vulnerability can be exploited by remote attackers with no required privileges or user interaction, accessible over the network with low attack complexity and no change in scope. Successful exploitation allows high-impact compromise of confidentiality, integrity, and availability through arbitrary code execution on the affected aaPanel instance.

Details on advisories, patches, and further technical analysis are available in the aaPanel GitHub repository at https://github.com/aapanel/aapanel and the vulnerability research repository at https://github.com/mbiesiad/vulnerability-research/tree/main/CVE-2026-29859.