CVE-2025-50461 Details

A deserialization vulnerability has been identified in Volcengine's Verl library version 3.0.0, specifically within the model_merger.py script. This issue arises when the 'fsdp' backend is used, as the script improperly handles user-supplied .pt files by calling torch.load() with weights_only set to False. This flaw allows attackers to execute arbitrary code by crafting a malicious model file and convincing a victim to load it. The vulnerability could be exploited by placing the harmful file in a directory that the script accesses, potentially leading to code execution with the user's privileges.

Users are advised to upgrade to Volcengine Verl version 0.5.0 or later, where this vulnerability has been addressed. Additionally, PyTorch should be updated to version 2.6.0 or later, which reduces deserialization risks by default.