CVE-2021-30639
Published: 12 July 2021
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.
Priority
Status
Package | Release | Status |
---|---|---|
tomcat9 Launchpad, Ubuntu, Debian |
jammy |
Needs triage
|
lunar |
Needs triage
|
|
bionic |
Needs triage
|
|
focal |
Needs triage
|
|
trusty |
Does not exist
|
|
upstream |
Needs triage
|
|
xenial |
Does not exist
|
|
groovy |
Ignored
(end of life)
|
|
impish |
Ignored
(end of life)
|
|
hirsute |
Ignored
(end of life)
|
|
kinetic |
Ignored
(end of life, was needs-triage)
|
|
mantic |
Needs triage
|
|
tomcat6 Launchpad, Ubuntu, Debian |
bionic |
Does not exist
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
hirsute |
Does not exist
|
|
trusty |
Needs triage
|
|
upstream |
Needs triage
|
|
xenial |
Needs triage
|
|
impish |
Does not exist
|
|
jammy |
Does not exist
|
|
kinetic |
Does not exist
|
|
lunar |
Does not exist
|
|
mantic |
Does not exist
|
|
tomcat7 Launchpad, Ubuntu, Debian |
bionic |
Needs triage
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
hirsute |
Does not exist
|
|
trusty |
Needs triage
|
|
upstream |
Needs triage
|
|
impish |
Does not exist
|
|
xenial |
Needs triage
|
|
jammy |
Does not exist
|
|
kinetic |
Does not exist
|
|
lunar |
Does not exist
|
|
mantic |
Does not exist
|
|
tomcat8 Launchpad, Ubuntu, Debian |
bionic |
Needs triage
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
hirsute |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Needs triage
|
|
xenial |
Needs triage
|
|
impish |
Does not exist
|
|
jammy |
Does not exist
|
|
kinetic |
Does not exist
|
|
lunar |
Does not exist
|
|
mantic |
Does not exist
|
Severity score breakdown
Parameter | Value |
---|---|
Base score | 7.5 |
Attack vector | Network |
Attack complexity | Low |
Privileges required | None |
User interaction | None |
Scope | Unchanged |
Confidentiality | None |
Integrity impact | None |
Availability impact | High |
Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
References
- https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-30639
- https://bz.apache.org/bugzilla/show_bug.cgi?id=65203
- https://github.com/apache/tomcat/commit/8ece47c4a9fb9349e8862c84358a4dd23c643a24 (9.0.45)
- https://github.com/apache/tomcat/commit/411caf29ac1c16e6ac291b6e5543b2371dbd25e2 (8.5.65)
- https://lists.apache.org/thread.html/rd84fae1f474597bdf358f5bdc0a5c453c507bd527b83e8be6b5ea3f4%40%3Cannounce.tomcat.apache.org%3E
- https://lists.apache.org/thread.html/r79a7c019712b39aedf7cf4da9276d80610f04441b2a4f6506cb2daaf@%3Cusers.tomcat.apache.org%3E
- https://lists.apache.org/thread.html/r79a7c019712b39aedf7cf4da9276d80610f04441b2a4f6506cb2daaf@%3Cdev.tomcat.apache.org%3E
- NVD
- Launchpad
- Debian