Hi, we're reviewing our logs, are we are ocasionally getting the
following stack traces:
09-Apr-2020 11:29:19.489 INFO [tomcat-http-81]
org.apache.coyote.http11.Http11Processor.service Error parsing HTTP
request header
Note: further occurrences of HTTP request parsing errors will be
logged at DEBUG level.
java.lang.IllegalArgumentException: Invalid character found in
the request target. The valid characters are defined in RFC 7230 and RFC
3986
at
org.apache.coyote.http11.Http11InputBuffer.parseRequestLine(Http11InputBuffer.java:488)
at
org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:260)
at
org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
at
org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868)
at
org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1594)
at
org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
at
java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1130)
at
java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:630)
at
org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
We understand this is a consequence of malformed requests, but we cannot
seem to pinpoint the cause. It seems these are clients outside of our
control (our servers are public-facing). The AccessLogValve does not log
these requests, so we cannot figure out what the request line is. Is
there any way logging could be improved in order to find out what is
causing this?
BTW, we're on Tomcat 9.0.33
*Manuel Dominguez Sarmiento*
