Forge (also called node-forge) is a native implementation of Transport Layer Security in JavaScript. Prior to 1.4.1, the affected implementation used pem.decode(), lib/pem.js, missing END line to process the relevant input or security decision. node-forge used polynomial-time regular expressions in pem.decode(), including when searching for a matching END line and parsing encapsulated headers. An unauthenticated attacker able to supply PEM input to any high-level parser could consume excessive CPU with a long malformed message and cause denial of service. This issue is fixed in version 1.4.1.
Weakness
The product does not properly control the allocation and maintenance of a limited resource.
Potential Mitigations
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.
Related Attack Patterns
- https://cwe.mitre.org/data/definitions/147.html
- https://cwe.mitre.org/data/definitions/227.html
- https://cwe.mitre.org/data/definitions/492.html
References
- https://github.com/digitalbazaar/forge/commit/412345db583cd28a9d23636d0d93e9f751b935f3
- https://github.com/digitalbazaar/forge/releases/tag/v1.4.1
- https://github.com/digitalbazaar/forge/security/advisories/GHSA-7wch-p9px-956x
- https://github.com/digitalbazaar/forge/security/advisories/GHSA-7wch-p9px-956x