In Spring Framework, versions 5.2.x prior to 5.2.15 and versions 5.3.x prior to 5.3.7, a WebFlux application is vulnerable to a privilege escalation: by (re)creating the temporary storage directory, a locally authenticated malicious user can read or modify files that have been uploaded to the WebFlux application, or overwrite arbitrary files with multipart request data.
In Spring Framework versions 5.2.0 - 5.2.8, 5.1.0 - 5.1.17, 5.0.0 - 5.0.18, 4.3.0 - 4.3.28, and older unsupported versions, the protections against RFD attacks from CVE-2015-5211 may be bypassed depending on the browser used through the use of a jsessionid path parameter.
Spring Framework, versions 5.2.x prior to 5.2.3 are vulnerable to CSRF attacks through CORS preflight requests that target Spring MVC (spring-webmvc module) or Spring WebFlux (spring-webflux module) endpoints. Only non-authenticated endpoints are vulnerable because preflight requests should not include credentials and therefore requests should fail authentication. However a notable exception to this are Chrome based browsers when using client certificates for authentication since Chrome sends TLS client certificates in CORS preflight requests in violation of spec requirements. No HTTP body can be sent or received as a result of this attack.
In Spring Framework, versions 5.2.x prior to 5.2.3, versions 5.1.x prior to 5.1.13, and versions 5.0.x prior to 5.0.16, an application is vulnerable to a reflected file download (RFD) attack when it sets a "Content-Disposition" header in the response where the filename attribute is derived from user supplied input.
Pivotal Spring Framework through 5.3.16 suffers from a potential remote code execution (RCE) issue if used for Java deserialization of untrusted data. Depending on how the library is implemented within a product, this issue may or not occur, and authentication may be required. NOTE: the vendor's position is that untrusted data is not an intended use case. The product's behavior will not be changed because some users rely on deserialization of trusted data.