Updated
Which AI model writes the most security and privacy bugs?
As of Sep 27, 2026, Claude Sonnet 5 had the highest rate of security and privacy bugs, 81% above the all-model rate (1.81), statistically tied with GPT-5.6 Luna and Claude Opus 5. GPT-5.6 Sol had the lowest, 42% below average (0.58), statistically tied with GPT-5.5.
| Rank | Model | Rate |
|---|---|---|
| 1= (statistically tied) | GPT-5.6 Sol | 0.58 |
| 2= (statistically tied) | GPT-5.5 | 0.62 |
| 3= (statistically tied) | Claude Fable 5.1 | 0.80 |
| 4= (statistically tied) | GPT-6 Astra | 0.82 |
| 5= (statistically tied) | Claude Fable 5 | 0.88 |
| 6= (statistically tied) | Claude Opus 4.8 | 1.08 |
| 7= (statistically tied) | GPT-5.6 Luna | 1.50 |
| 8= (statistically tied) | Claude Opus 5 | 1.53 |
| 9= (statistically tied) | Claude Sonnet 5 | 1.81 |
1.00 = all-model rate · lower is better · = statistically tied