Epoch: Open-Weight GLM 5.3 Hacks Six Firefox Versions for ~$1,000 Each; Claude Fable 5.2 Sets ECI Record

Epoch AI · rss · 2026-11-12

Epoch AI's latest brief covers several major findings:

Open-weight cyber capability diffusion: In sandbox experiments, GLM 5.3 autonomously compromised six recent Firefox versions (200M+ users) for $1,000 each, exploiting the "patch gap" by reverse-engineering attacks from unreleased security fixes. Attack pages could read visitors' files. Chrome resisted, but better prompting or stronger models could change that.
Claude Fable 5.2 sets record: Scored 174 on the Epoch Capabilities Index, beating GPT-6 Astra's 169 and exceeding the pre-existing reasoning-model trend.
ECI methodology upgrade: Shifted from frequentist to Bayesian scoring, enabling probabilistic comparisons (e.g., Astra has a 72% probability of beating Claude Opus 5.5).
Compute doubling every 9 months: Quarterly capacity additions have grown 2.5× per year since 2024; Broadcom doubled TPU shipments in one quarter to nearly 2M H100-equivalents, serving Google and Anthropic.
Where chips land: 72% of the 27.4M H100e delivered globally since 2022 went to the US, 10% to China, 5% to the EU. Huawei's Horinger data center (286MW) holds roughly 7% of SpaceX Colossus 2's compute.
Biology LLM adoption: 17% of biology preprints now acknowledge LLM use, nearly matching AlphaFold-class tools at 19%.

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