CVE-2025-56704
Lepton-Cms Leptoncms 7.3.0
Raw vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HSummary
CVE-2025-56704 is a high-severity Unrestricted Upload of File with Dangerous Type (CWE-434) vulnerability in Lepton-Cms Leptoncms. Its CVSS base score is 8.8 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 49% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified map to SI-3 (Malicious Code Protection) and CM-7 (Least Functionality) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2025-56704, published on 2025-12-09, is an arbitrary file upload vulnerability in LeptonCMS version 7.3.0. The flaw stems from a lack of proper validation for uploaded files, earning a CVSS 3.1 base score of 8.8 (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H) and mapping to CWE-434 (Unrestricted Upload of File with Dangerous Type).
An authenticated attacker with low privileges can exploit the vulnerability remotely over the network with low complexity and no user interaction required. By uploading a specially crafted ZIP/PHP file, the attacker achieves arbitrary code execution, resulting in high impacts to confidentiality, integrity, and availability.
Advisories and additional details on the vulnerability, including potential mitigations, are documented in the vendor notice at http://lepton.com and technical reports available at https://github.com/Kayi626/Vulns/blob/UserAccount/LEPTON_CMS_7.3.0_File_Upload_A.pdf, https://github.com/Kayi626/Vulns/blob/UserAccount/LEPTON_CMS_7.3.0_File_Upload_B.pdf, and https://github.com/Kayi626/Vulns/blob/UserAccount/LEPTON_CMS_7.3.0_File_Upload_C.pdf.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2025-202289
Vulnerability Data
LeptonCMS version 7.3.0 contains an arbitrary file upload vulnerability, which is caused by the lack of proper validation for uploaded files. An authenticated attacker can exploit this vulnerability by uploading a specially crafted ZIP/PHP file to execute arbitrary code.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V5.1.1
Mitigating Controls (NIST 800-53 r5) AI
Malicious-code protection at entry points blocks dangerous file types from being accepted and executed.
Least functionality restricts the file types and automatic processing capabilities the system will accept.
Mobile-code controls define, authorize, and block unacceptable uploaded code before automatic processing occurs.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Restricting execution of unauthorized software directly blocks dangerous uploaded files from running.
Hardened configuration baselines can enforce allowed file types and processing rules.
Secure development practices include input validation and file-type restrictions that prevent this weakness.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Configuration and acceptance testing verify that file-upload handling enforces allowed types and does not permit dangerous content to be stored or executed.
Secure-coding guidelines and security testing explicitly address restrictions on allowed file types and upload handling, reducing the risk that dangerous file uploads are accepted without validation.
Mandated testing for malicious content and known vulnerabilities reduces the likelihood that an outsourced component will contain or accept dangerous file types that could later be uploaded or executed.
Application allow-listing and pre-use scanning of received files directly blocks the introduction of executable content that has not been vetted, eliminating the primary vector for unrestricted dangerous file uploads.