Overview
In today’s digital age, the importance of robust cybersecurity practices cannot be overstated. The exposure of vulnerabilities can lead to serious consequences, such as data breaches and system compromises. One such vulnerability is CVE-2025-50900, a critical security flaw found in getrebuild/rebuild 4.0.4. This vulnerability can potentially allow unauthenticated attackers to gain access to sensitive information or escalate their privileges within a system-an alarming prospect for organizations that prioritize data security and integrity.
The vulnerability lies within the source code class com.rebuild.web.RebuildWebInterceptor and can affect any organization or individual that relies on a version of the software that hasn’t been patched or updated. The severity of the issue is underscored by its Common Vulnerability Scoring System (CVSS) severity score of 9.8, which places it in the critical range.
Vulnerability Summary
CVE ID: CVE-2025-50900
Severity: Critical (9.8/10)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: System compromise and potential data leakage
Affected Products
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Product | Affected Versions
getrebuild/rebuild | 4.0.4
How the Exploit Works
The vulnerability operates through the preHandle function in the RebuildWebInterceptor class. Here, the filter code uses CodecUtils.urlDecode(request.getRequestURI()) to acquire the URL-decoded request path. The code then checks if the path ends with /error. If it does, the Interceptor is skipped. Otherwise, the code redirects to the /user/login API.
This opens a loophole for unauthenticated attackers. They can manipulate the request path to end with /error, thereby bypassing the Interceptor and gaining access to sensitive information or even escalating their privileges within the system.
Conceptual Example Code
Below is a conceptual example of how this vulnerability might be exploited:
GET /path/to/sensitive/data/error HTTP/1.1
Host: target.example.comIn this example, the attacker crafts a GET request to a sensitive data path and appends “/error” at the end. This bypasses the security Interceptor and allows the attacker to access the confidential information without needing to authenticate themselves first.
Mitigation Guidance
To mitigate this critical vulnerability, users are advised to apply the vendor patch as soon as it becomes available. In the meantime, the use of a Web Application Firewall (WAF) or an Intrusion Detection System (IDS) can serve as a temporary defense measure. It’s crucial to remember, however, that these are interim solutions and cannot replace the security offered by the official vendor patch.