If an async request was completed by the application at the same time as the container triggered the async timeout, a race condition existed that could result in a user seeing a response intended for a different user. An additional issue was present in the NIO and NIO2 connectors that did not correctly track the closure of the connection when an async request was completed by the application and timed out by the container at the same time. This could also result in a user seeing a response intended for another user. Versions Affected: Apache Tomcat 9.0.0.M9 to 9.0.9 and 8.5.5 to 8.5.31.
The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Tomcat | Apache | 8.5.5 (including) | 8.5.31 (including) |
| Tomcat | Apache | 9.0.1 (including) | 9.0.9 (including) |
| Tomcat | Apache | 9.0.0 (including) | 9.0.0 (including) |
| Tomcat | Apache | 9.0.0-milestone10 (including) | 9.0.0-milestone10 (including) |
| Tomcat | Apache | 9.0.0-milestone11 (including) | 9.0.0-milestone11 (including) |
| Tomcat | Apache | 9.0.0-milestone12 (including) | 9.0.0-milestone12 (including) |
| Tomcat | Apache | 9.0.0-milestone13 (including) | 9.0.0-milestone13 (including) |
| Tomcat | Apache | 9.0.0-milestone14 (including) | 9.0.0-milestone14 (including) |
| Tomcat | Apache | 9.0.0-milestone15 (including) | 9.0.0-milestone15 (including) |
| Tomcat | Apache | 9.0.0-milestone16 (including) | 9.0.0-milestone16 (including) |
| Tomcat | Apache | 9.0.0-milestone17 (including) | 9.0.0-milestone17 (including) |
| Tomcat | Apache | 9.0.0-milestone18 (including) | 9.0.0-milestone18 (including) |
| Tomcat | Apache | 9.0.0-milestone19 (including) | 9.0.0-milestone19 (including) |
| Tomcat | Apache | 9.0.0-milestone20 (including) | 9.0.0-milestone20 (including) |
| Tomcat | Apache | 9.0.0-milestone21 (including) | 9.0.0-milestone21 (including) |
| Tomcat | Apache | 9.0.0-milestone22 (including) | 9.0.0-milestone22 (including) |
| Tomcat | Apache | 9.0.0-milestone23 (including) | 9.0.0-milestone23 (including) |
| Tomcat | Apache | 9.0.0-milestone24 (including) | 9.0.0-milestone24 (including) |
| Tomcat | Apache | 9.0.0-milestone25 (including) | 9.0.0-milestone25 (including) |
| Tomcat | Apache | 9.0.0-milestone26 (including) | 9.0.0-milestone26 (including) |
| Tomcat | Apache | 9.0.0-milestone27 (including) | 9.0.0-milestone27 (including) |
| Tomcat | Apache | 9.0.0-milestone9 (including) | 9.0.0-milestone9 (including) |
| Red Hat Enterprise Linux 8 | RedHat | pki-deps:10.6-8000020190524054914.55190bc5 | * |
| Red Hat JBoss Web Server 5.0 | RedHat | tomcat | * |
| Red Hat JBoss Web Server 5.0 on RHEL 6 | RedHat | jws5-tomcat-0:9.0.7-12.redhat_12.1.el6jws | * |
| Red Hat JBoss Web Server 5.0 on RHEL 7 | RedHat | jws5-tomcat-0:9.0.7-12.redhat_12.1.el7jws | * |
| Tomcat8 | Ubuntu | bionic | * |
| Tomcat8 | Ubuntu | esm-apps/bionic | * |
| Tomcat8 | Ubuntu | upstream | * |
A race condition occurs within concurrent environments, and it is effectively a property of a code sequence. Depending on the context, a code sequence may be in the form of a function call, a small number of instructions, a series of program invocations, etc. A race condition violates these properties, which are closely related:
A race condition exists when an “interfering code sequence” can still access the shared resource, violating exclusivity. The interfering code sequence could be “trusted” or “untrusted.” A trusted interfering code sequence occurs within the product; it cannot be modified by the attacker, and it can only be invoked indirectly. An untrusted interfering code sequence can be authored directly by the attacker, and typically it is external to the vulnerable product.