XStream is an open source java library to serialize objects to XML and back again. Versions prior to 1.4.19 may allow a remote attacker to allocate 100% CPU time on the target system depending on CPU type or parallel execution of such a payload resulting in a denial of service only by manipulating the processed input stream. XStream 1.4.19 monitors and accumulates the time it takes to add elements to collections and throws an exception if a set threshold is exceeded. Users are advised to upgrade as soon as possible. Users unable to upgrade may set the NO_REFERENCE mode to prevent recursion. See GHSA-rmr5-cpv2-vgjf for further details on a workaround if an upgrade is not possible.
The product does not properly control the allocation and maintenance of a limited resource.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Jenkins | Jenkins | * | 2.319.3 (excluding) |
| Jenkins | Jenkins | 2.321 (including) | 2.334 (excluding) |
| Red Hat Fuse 7.11 | RedHat | xstream | * |
| Red Hat OpenShift Container Platform 3.11 | RedHat | jenkins-0:2.319.3.1650348949-1.el7 | * |
| RHINT Camel-Q 2.7 | RedHat | xstream | * |
| Libxstream-java | Ubuntu | bionic | * |
| Libxstream-java | Ubuntu | focal | * |
| Libxstream-java | Ubuntu | impish | * |
| Libxstream-java | Ubuntu | kinetic | * |
| Libxstream-java | Ubuntu | lunar | * |
| Libxstream-java | Ubuntu | mantic | * |
| Libxstream-java | Ubuntu | oracular | * |
| Libxstream-java | Ubuntu | trusty/esm | * |
Mitigation of resource exhaustion attacks requires that the target system either:
The first of these solutions is an issue in itself though, since it may allow attackers to prevent the use of the system by a particular valid user. If the attacker impersonates the valid user, they may be able to prevent the user from accessing the server in question.
The second solution is simply difficult to effectively institute – and even when properly done, it does not provide a full solution. It simply makes the attack require more resources on the part of the attacker.