The following code points hide exceptions. A good description of the issue can be found here https://wiki.sei.cmu.edu/confluence/display/java/ERR04-.+Do+not+complete+abruptly+from+a+finally+block

• https://github.com/undertow-io/undertow/blob/2.2.8.Final/core/src/main/java/io/undertow/protocols/http2/Http2PushBackParser.java#L75
• https://github.com/undertow-io/undertow/blob/2.2.8.Final/core/src/main/java/io/undertow/security/impl/FormAuthenticationMechanism.java#L137
• https://github.com/undertow-io/undertow/blob/2.2.8.Final/core/src/main/java/io/undertow/server/protocol/ajp/AjpServerRequestConduit.java#L333

Please include the method signature in your analysis - it declares a IOException.