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CVE-2021-30639 A vulnerability in Apache Tomcat allows an attacker to remotely trigger a denial of service
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. This issue affects Apache Tomcat 10.0.3 to 10.0.4; 9.0.44; 8.5.64.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Apache Tomcat | Versions not published |
References
- lists.apache.org lists.apache.org
- [tomcat-users] 20210712 RE: [SECURITY] CVE-2021-30639 Apache Tomcat DoS lists.apache.org
- [tomcat-dev] 20210712 RE: [SECURITY] CVE-2021-30639 Apache Tomcat DoS lists.apache.org
- security.netapp.com security.netapp.com
- kc.mcafee.com kc.mcafee.com
- www.oracle.com www.oracle.com
- GLSA-202208-34 security.gentoo.org
Timeline
- Published
- Last modified
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