Summary
An unrestricted file upload vulnerability in ShowDoc caused by improper validation of file extension allows execution of arbitrary PHP, leading to remote code execution. This issue affects ShowDoc: before 2.8.7.
Impact
The application accepts file uploads without adequately restricting the file type or content. Typical impact: remote code execution if the uploaded file can be served and executed on the server.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Remediation advice
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is CVE-2025-0520? CVE-2025-0520 is a critical-severity unrestricted upload of dangerous file types vulnerability in showdoc/showdoc (composer), affecting versions < 2.8.7. It is fixed in 2.8.7. The application accepts file uploads without adequately restricting the file type or content.
- Which versions of showdoc/showdoc are affected by CVE-2025-0520? showdoc/showdoc (composer) versions < 2.8.7 is affected.
- Is there a fix for CVE-2025-0520? Yes. CVE-2025-0520 is fixed in 2.8.7. Upgrade to this version or later.
- Is CVE-2025-0520 exploitable, and should I be worried? Whether CVE-2025-0520 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2025-0520 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2025-0520? Upgrade
showdoc/showdocto 2.8.7 or later.