rootvector2 opened a new pull request, #789: URL: https://github.com/apache/commons-vfs/pull/789
`FtpsClientFactory.createClient` installs a trust manager that validates the certificate chain (`getTrustManager` defaults to `TrustManagerUtils.getValidateServerCertificateTrustManager`) but never enables TLS endpoint identity checking on the `FTPSClient`, so commons-net never verifies that the certificate matches the connected host. A man-in-the-middle holding any certificate the client already trusts (for example a valid certificate for an unrelated domain) can impersonate the FTPS server on the control and data channels. Found while auditing the ftps provider against the http4/http5 TLS handling, which already verifies the host name. The fix calls `FTPSClient.setEndpointCheckingEnabled` in `createClient`, enabled by default through a new `FtpsFileSystemConfigBuilder` option so it can be turned off for a server whose certificate cannot carry the host name. The added `FtpsEndpointCheckingTest` connects through the loopback IP to the `CN=localhost` test server: the connection is rejected with verification on and accepted with it off, and it fails without this change. - [x] Read the [contribution guidelines](CONTRIBUTING.md) for this project. - [x] Read the [ASF Generative Tooling Guidance](https://www.apache.org/legal/generative-tooling.html) if you use Artificial Intelligence (AI). - [x] I used AI to create any part of, or all of, this pull request. Which AI tool was used to create this pull request, and to what extent did it contribute? An AI coding assistant (Claude) helped locate the missing host-name check, draft the fix and test, and write this description; I reviewed and verified all changes and the build locally. - [x] Run a successful build using the default [Maven](https://maven.apache.org/) goal with `mvn`; that's `mvn` on the command line by itself. - [x] Write unit tests that match behavioral changes, where the tests fail if the changes to the runtime are not applied. This may not always be possible, but it is a best practice. - [x] Write a pull request description that is detailed enough to understand what the pull request does, how, and why. - [x] Each commit in the pull request should have a meaningful subject line and body. Note that a maintainer may squash commits during the merge process. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
