CVE-2025-4893 is a medium-severity path traversal vulnerability found in the CoinExchange_CryptoExchange_Java application developed by jammy928. The flaw exists in the uploadLocalImage function within the UploadFileUtil.java file, which is part of the file upload endpoint component. Specifically, the vulnerability arises from improper validation or sanitization of the filename argument, allowing an attacker to manipulate this parameter to perform a path traversal attack. This enables the attacker to access or overwrite files outside the intended directory on the server's filesystem. The vulnerability can be exploited remotely without requiring user interaction or authentication, increasing the risk of unauthorized file access or modification. The CVSS 4.0 vector indicates the attack vector is network-based (AV:N), with low attack complexity (AC:L), no privileges required (PR:L), and no user interaction (UI:N). The impact on confidentiality, integrity, and availability is low to limited, which aligns with the medium severity rating and a CVSS score of 5.3. The affected version is identified by a specific commit hash (8adf508b996020d3efbeeb2473d7235bd01436fa), and no versioning scheme is used by the product, complicating patch management. Although no public exploits are currently known in the wild, the vulnerability has been publicly disclosed, which may lead to exploitation attempts. The lack of patch links suggests that no official fix has been released yet, emphasizing the need for immediate mitigation measures by users of this software.

For European organizations using CoinExchange_CryptoExchange_Java, this vulnerability poses a risk of unauthorized access to sensitive files on the server hosting the application. Given that the product is related to cryptocurrency exchange platforms, the confidentiality and integrity of critical financial data, user credentials, and transaction records could be compromised if exploited. This could lead to data breaches, financial fraud, or disruption of exchange services. The ability to perform path traversal remotely without authentication increases the attack surface, especially for internet-facing deployments. However, the limited impact on availability and the medium severity rating suggest that while the threat is significant, it may not lead to complete system compromise or denial of service. European organizations operating cryptocurrency exchanges or related financial services should be particularly vigilant, as regulatory frameworks such as GDPR impose strict requirements on data protection and breach notification. Exploitation could result in reputational damage, regulatory penalties, and financial losses.

1. Immediate code review and validation: Organizations should audit the uploadLocalImage function and any file upload endpoints to ensure proper validation and sanitization of filename inputs, rejecting any path traversal characters such as '../' or absolute paths. 2. Implement allowlists: Restrict file uploads to specific directories and enforce strict allowlists for filenames and extensions. 3. Use secure APIs: Replace any direct file system access with secure APIs that enforce sandboxing and prevent directory traversal. 4. Apply access controls: Ensure that the application runs with the least privileges necessary, limiting the impact of any file access. 5. Monitor logs: Enable detailed logging and monitoring for suspicious file access patterns or unexpected file modifications. 6. Network segmentation: Isolate the application servers from critical infrastructure to limit lateral movement in case of compromise. 7. Patch management: Engage with the vendor or development community to obtain or develop patches addressing this vulnerability. 8. Incident response readiness: Prepare to respond to potential exploitation attempts by having forensic and remediation procedures in place. 9. Consider deploying Web Application Firewalls (WAFs) with rules to detect and block path traversal attempts targeting the upload endpoints.