CVE-2025-57697 is a medium-severity arbitrary file read vulnerability found in AstrBot Project version 3.5.22. The flaw resides in the _encode_image_bs64 function defined in entities.py, which processes user-supplied image paths by opening the specified file and returning its content as a base64-encoded string. Critically, this function lacks proper validation or sanitization of the file path input, allowing attackers to craft malicious URLs that specify arbitrary file paths on the server. This leads to unauthorized reading of any file accessible by the application’s user privileges, potentially exposing sensitive configuration files, credentials, or other confidential data. The vulnerability is exploitable remotely over the network without requiring authentication or user interaction, as indicated by the CVSS vector (AV:N/AC:L/PR:N/UI:N). The CVSS score of 6.5 reflects the moderate impact on confidentiality and low impact on availability, with no integrity impact. Although no known exploits are currently reported in the wild and no patches have been released, the vulnerability represents a significant risk due to the ease of exploitation and potential data leakage. The underlying weakness aligns with CWE-125 (Out-of-bounds Read), highlighting improper input validation and unsafe file handling. Organizations using AstrBot v3.5.22 or similar versions should be aware of this vulnerability and take proactive steps to mitigate risk.

For European organizations, this vulnerability poses a risk of sensitive data exposure, including internal configuration files, credentials, or proprietary information, which could be leveraged for further attacks such as privilege escalation or lateral movement. Industries handling critical infrastructure, finance, healthcare, or government data are particularly vulnerable due to the potential confidentiality breach. The lack of authentication requirement means attackers can exploit this vulnerability remotely without prior access, increasing the attack surface. Although the impact on system availability is low, the confidentiality compromise can lead to regulatory non-compliance (e.g., GDPR), reputational damage, and financial losses. Organizations relying on AstrBot or similar vulnerable components in their software stack should prioritize assessment and remediation to prevent data leakage incidents.

Specific mitigation steps include: 1) Implement strict validation and sanitization of all user-supplied file path inputs in the _encode_image_bs64 function to ensure only legitimate image files within designated directories are processed. 2) Employ allowlisting of acceptable file paths or extensions and reject any input that attempts directory traversal or references sensitive system files. 3) Run the application with the least privilege necessary, restricting file system permissions to limit accessible files. 4) Monitor and log all requests to the vulnerable endpoint to detect anomalous or suspicious file access patterns. 5) If possible, isolate the image processing functionality in a sandboxed environment to contain potential exploitation. 6) Engage with the AstrBot project maintainers or community to obtain or contribute patches addressing this vulnerability. 7) Conduct regular security audits and code reviews focusing on input handling and file operations. 8) Educate developers on secure coding practices related to file I/O and input validation.