REXML is an XML toolkit for Ruby. The REXML gem 3.3.2 has a DoS vulnerability when it parses an XML that has many entity expansions with SAX2 or pull parser API. The REXML gem 3.3.3 or later include the patch to fix the vulnerability.
The product does not properly control the allocation and maintenance of a limited resource.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Rexml | Ruby-lang | * | 3.3.3 (excluding) |
| Red Hat Enterprise Linux 8 | RedHat | ruby:3.3-8100020240906074654.489197e6 | * |
| Red Hat Enterprise Linux 8 | RedHat | ruby:3.1-8100020250407112943.489197e6 | * |
| Red Hat Enterprise Linux 8 | RedHat | pcs-0:0.10.18-2.el8_10.2 | * |
| Red Hat Enterprise Linux 8.6 Telecommunications Update Service | RedHat | pcs-0:0.10.12-6.el8_6.6 | * |
| Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions | RedHat | pcs-0:0.10.12-6.el8_6.6 | * |
| Red Hat Enterprise Linux 8.8 Extended Update Support | RedHat | pcs-0:0.10.15-4.el8_8.3 | * |
| Red Hat Enterprise Linux 9 | RedHat | ruby:3.3-9040020240906110954.9 | * |
| Red Hat Enterprise Linux 9 | RedHat | ruby:3.1-9050020250404144903.9 | * |
| Jruby | Ubuntu | focal | * |
| Jruby | Ubuntu | oracular | * |
| Jruby | Ubuntu | trusty/esm | * |
| Ruby2.3 | Ubuntu | esm-infra/xenial | * |
| Ruby2.5 | Ubuntu | esm-infra/bionic | * |
| Ruby2.7 | Ubuntu | esm-infra/focal | * |
| Ruby2.7 | Ubuntu | focal | * |
| Ruby3.0 | Ubuntu | jammy | * |
| Ruby3.2 | Ubuntu | noble | * |
| Ruby3.3 | Ubuntu | devel | * |
| Ruby3.3 | Ubuntu | oracular | * |
| Ruby3.3 | Ubuntu | plucky | * |
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.