Just 125 Poisoned Samples Can Backdoor Qwen2.5-7B

Researchers showed that poisoning just 125 fine-tuning samples can backdoor Qwen2.5-7B, making it execute malicious code and steal credentials when a secret trigger phrase appears, sparking debate over open-model download security.

2026-10-26 ~ 2026-10-27 · 2 related posts

• 125 poisoned examples planted a code-stealing backdoor in Qwen 2.5-7B — GarrisonLovely · 2026-10-26
• 125 poisoned samples backdoored Qwen2.5-7B — and open-weight supply chain risks debated — lxrjl · 2026-10-27