A vulnerability in parisneo/lollms-webui v13 arises from the servers handling of multipart boundaries in file uploads. The server does not limit or validate the length of the boundary or the characters appended to it, allowing an attacker to craft requests with excessively long boundaries, leading to resource exhaustion and eventual denial of service (DoS). Despite an attempted patch in commit 483431bb, which blocked hyphen characters from being appended to the multipart boundary, the fix is insufficient. The server remains vulnerable if other characters (e.g., 4, a) are used instead of hyphens. This allows attackers to exploit the vulnerability using different characters, causing resource exhaustion and service unavailability.
The product does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Lollms_web_ui | Lollms | 13 (including) | 13 (including) |
Limited resources include memory, file system storage, database connection pool entries, and CPU. If an attacker can trigger the allocation of these limited resources, but the number or size of the resources is not controlled, then the attacker could cause a denial of service that consumes all available resources. This would prevent valid users from accessing the product, and it could potentially have an impact on the surrounding environment. For example, a memory exhaustion attack against an application could slow down the application as well as its host operating system. There are at least three distinct scenarios which can commonly lead to resource exhaustion:
Resource exhaustion problems are often result due to an incorrect implementation of the following situations:
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.