| Name | CVE-2021-30639 |
| 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. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| tomcat7 (PTS) | jessie, jessie (lts) | 7.0.56-3+really7.0.109-1+deb8u6 | fixed |
| stretch | 7.0.75-1 | fixed | |
| tomcat8 (PTS) | jessie, jessie (lts) | 8.0.14-1+deb8u28 | fixed |
| stretch (security) | 8.5.54-0+deb9u8 | fixed | |
| stretch (lts), stretch | 8.5.54-0+deb9u15 | fixed | |
| tomcat9 (PTS) | buster (security), buster, buster (lts) | 9.0.31-1~deb10u12 | fixed |
| bullseye (security), bullseye | 9.0.43-2~deb11u10 | fixed | |
| bookworm | 9.0.70-2 | fixed | |
| sid, trixie | 9.0.95-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| tomcat7 | source | (unstable) | (not affected) | |||
| tomcat8 | source | jessie | (not affected) | |||
| tomcat8 | source | stretch | (not affected) | |||
| tomcat8 | source | (unstable) | (unfixed) | |||
| tomcat9 | source | (unstable) | (not affected) |
- tomcat9 <not-affected> (Vulnerable code introduced later in 9.0.44)
[stretch] - tomcat8 <not-affected> (Vulnerable code was introduced later)
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)
- tomcat7 <not-affected> (The vulnerable code was introduced later)
[jessie] - tomcat8 <not-affected> (The vulnerable code was introduced later)