CVE-2021-43980

Publication date 28 September 2022

Last updated 11 July 2025


Ubuntu priority

Cvss 3 Severity Score

3.7 · Low

Score breakdown

The simplified implementation of blocking reads and writes introduced in Tomcat 10 and back-ported to Tomcat 9.0.47 onwards exposed a long standing (but extremely hard to trigger) concurrency bug in Apache Tomcat 10.1.0 to 10.1.0-M12, 10.0.0-M1 to 10.0.18, 9.0.0-M1 to 9.0.60 and 8.5.0 to 8.5.77 that could cause client connections to share an Http11Processor instance resulting in responses, or part responses, to be received by the wrong client.

Status

Package Ubuntu Release Status
tomcat9 25.04 plucky
Not affected
24.10 oracular Ignored end of life, was needs-triage
24.04 LTS noble
Not affected
23.10 mantic Ignored end of life, was needs-triage
23.04 lunar Ignored end of life, was needs-triage
22.10 kinetic Ignored end of life, was needs-triage
22.04 LTS jammy
Vulnerable
20.04 LTS focal
Vulnerable
18.04 LTS bionic
Vulnerable
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
tomcat6 22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic Not in release
16.04 LTS xenial
Needs evaluation
14.04 LTS trusty
Needs evaluation
tomcat7 22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic
Needs evaluation
16.04 LTS xenial
Needs evaluation
14.04 LTS trusty
Needs evaluation
tomcat8 22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic
Vulnerable
16.04 LTS xenial
Needs evaluation
14.04 LTS trusty Not in release

Severity score breakdown

Parameter Value
Base score 3.7 · Low
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Scope Unchanged
Confidentiality Low
Integrity impact None
Availability impact None
Vector CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N