{"schemaVersion":3,"id":"CVE-2021-30639","aliases":["UBUNTU-CVE-2021-30639","GHSA-44qp-qhfv-c7f6","BIT-tomcat-2021-30639"],"status":"published","duplicateOf":null,"title":null,"description":"A vulnerability in Apache Tomcat allows an attacker to remotely trigger a denial of service. An error introduced as part of a change to improve error handling during non-blocking I/O meant that the error flag associated with the Request object was not reset between requests. This meant that once a non-blocking I/O error occurred, all future requests handled by that request object would fail. Users were able to trigger non-blocking I/O errors, e.g. by dropping a connection, thereby creating the possibility of triggering a DoS. Applications that do not use non-blocking I/O are not exposed to this vulnerability. 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