ResourceCacheService builds a file name from an incoming URI fragment without sanitizing path separators or '..' sequences, then writes data to the constructed path. This flaw allows an attacker to override any file under the resource parent folder, potentially replacing or corrupting critical files and compromising system integrity. The vulnerability is a path traversal weakness that can be exploited to achieve arbitrary file write.

Spring AI software is affected. Versions 2.0.0, 1.1.0 through 1.1.8, and 1.0.9 and earlier are vulnerable.

The CVSS score of 5.9 classifies the issue as moderate severity, while the EPSS score is currently unavailable and the vulnerability is not listed in the CISA KEV catalog. The likely attack vector is an HTTP request to the ResourceCacheService with a crafted URI fragment that resolves to an unauthorized file path. Successful exploitation requires access to the service endpoint and the ability to upload data, but it does not require remote code execution or elevated privileges beyond write permissions in the resource folder.