A vulnerability in the LangChainLLM class of the run-llama/llama_index repository, version v0.12.5, allows for a Denial of Service (DoS) attack. The stream_complete method executes the llm using a thread and retrieves the result via the get_response_gen method of the StreamingGeneratorCallbackHandler class. If the thread terminates abnormally before the _llm.predict is executed, there is no exception handling for this case, leading to an infinite loop in the get_response_gen function. This can be triggered by providing an input of an incorrect type, causing the thread to terminate and the process to continue running indefinitely.
{
"cwe_ids": [
"CWE-755",
"CWE-835"
],
"github_reviewed": true,
"github_reviewed_at": "2025-03-21T17:40:52Z",
"nvd_published_at": "2025-03-20T10:15:29Z",
"severity": "HIGH"
}