Security Resilience

CVE-2025-51489

XSS in Moonshine ≤ 3.12.5

Public PoCXSS
Published
19 August 2025
Modified
17 June 2026
Patch / advisory
View advisory
CVSS Score v3.1 5.4
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
EPSS Score 0.0034 27th percentile
Risk Priority 41 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2025-51489 is a medium-severity Cross-site Scripting (CWE-79) vulnerability in Moonshine Moonshine. Its CVSS base score is 5.4 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Browser Session Hijacking (T1185); ranked at the 27th 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 map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

A05:2025 InjectionA06:2025 Insecure Design

EU & UK References

Vulnerability Data

A Stored Cross-Site Scripting (XSS) vulnerability exists in MoonShine version < 3.12.5, allowing remote attackers to upload a malicious SVG file when creating/updating an Article and correctly execute arbitrary JavaScript when the file link is opened.

CWE(s)
CWE-79CWE-434

Related Threats

MITRE ATT&CK Enterprise Techniques

T1505.003 Web Shell Persistence
Adversaries may backdoor web servers with web shells to establish persistent access to systems.
attack.mitre.org →
T1059 Command and Scripting Interpreter Execution
Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries.
attack.mitre.org →
T1185 Browser Session Hijacking Collection
Adversaries may take advantage of security vulnerabilities and inherent functionality in browser software to change content, modify user-behaviors, and intercept information as part of various browser session hijacking techniques.
attack.mitre.org →
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 →
T1505 Server Software Component Persistence
Adversaries may abuse legitimate extensible development features of servers to establish persistent access to systems.
attack.mitre.org →
T1539 Steal Web Session Cookie Credential Access
An adversary may steal web application or service session cookies and use them to gain access to web applications or Internet services as an authenticated user without needing credentials.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-27605Shared CWE-434, CWE-79
CVE-2026-54087Shared CWE-434, CWE-79
CVE-2026-25648Shared CWE-434, CWE-79
CVE-2023-30962Shared CWE-434, CWE-79
CVE-2024-34906Shared CWE-434, CWE-79
CVE-2025-67289Shared CWE-434, CWE-79
CVE-2024-12042Shared CWE-434, CWE-79
CVE-2023-50717Shared CWE-434, CWE-79
CVE-2026-65986Shared CWE-434, CWE-79
CVE-2026-105862Shared CWE-434, CWE-79

Affected Assets

moonshine
moonshine
≤ 3.12.5

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V5.1.1
  • V1.1.2
  • V1.3.2

Mitigating Controls (NIST 800-53 r5) AI

SA-11 Developer Testing and Evaluation good match

Developer testing and evaluation can discover missing or incorrect input neutralization through targeted web-application tests.

SI-10 Information Input Validation good match

Input validation directly enforces neutralization of untrusted data before it reaches web output generation.

SI-15 Information Output Filtering good match

Output filtering can catch or sanitize unneutralized script content before it is served to users.

SI-3 Malicious Code Protection good match

Malicious-code protection at entry points blocks dangerous file types from being accepted and executed.

CM-7 Least Functionality partial match

Least functionality restricts the file types and automatic processing capabilities the system will accept.

SC-18 Mobile Code partial match

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.

PR.PS-05 mostly match
blocks

Restricting execution of unauthorized software directly blocks dangerous uploaded files from running.

PR.PS-06 mostly match
blocks

Secure SDLC practices directly target introduction of XSS via coding standards/testing (mostly), yet the single broad outcome leaves many specific neutralization vectors unaddressed (partial).

PR.PS-01 partial match
blocks

Hardened configuration baselines can enforce allowed file types and processing rules.

PR.PS-02 partial match
blocks

Patching and EOL replacement can remediate known XSS instances in libraries or frameworks (partial) but do nothing to enforce input neutralization in application code (none).

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.

A.8.29 Security testing in development and acceptance mostly match
finds

Secure-coding testing and automated code-analysis tools are applied to detect improper neutralization of script-related content during web-page generation.

A.8.28 Secure coding partial match
prevents

Secure-coding standards, SAST scans and removal of insecure code samples together eliminate the failure to neutralize script content that produces cross-site scripting flaws.

References