DeepSeek V4 Pro was the best (and most expensive) LLM I tested with Strix a few months ago. After the heartbreaking results of its smaller sibling, DeepSeek V4 Flash 0731, in my HTB-Challenger tests, I was curious to see how the Pro version would handle the new challenges.


HTB-Challenger Benchmark

This blog post is part of a series of tests for the HTB-Challenger BenchmarkThe HTB-Challenger Benchmark evaluates LLMs’ ability to find and exploit security vulnerabilities. It tests models against selected Hack The Box challenges of varying difficulty and measures their performance. For more information, visit the HTB-Challenger Benchmark page. . See the benchmark results page for all results and the benchmark methodology to learn how the benchmark is calculated.


The results of DeepSeek V4 Pro in my testing were, well, not great and not terrible. On the one hand, it didn’t have the basic flaws I observed when testing DeepSeek V4 Flash 0731: it didn’t submit any incorrect flags, and it used the available tools without any issues. On the other hand, its final score was comparable to that of GPT-5.6 Luna, whose median cost per test was 17 times lower.

The performance gap between DeepSeek V4 Pro and the leaders of my benchmark was also quite large. I’m afraid that’s a sign of just how quickly things have progressed over the last few months. DeepSeek V4 Pro was released four months ago, which feels like an eternity now that we’re getting better and better models almost every month.


HTB-Challenger Benchmark LLM model card

Cost vs. Benchmark Score

The highlighted point is this model. Models closer to the upper-left achieve a higher benchmark score at a lower median cost per challenge.

Cost vs. Benchmark Score with this model highlighted

Overall benchmark results

  • Number of challenges: 16
  • Number of solved challenges: 8
  • Number of false positives: 0
  • Runs where the model gave up: 0
  • Runs that reached the step or cost limit: 8
  • Runs where the model got stuck: 0
  • Benchmark score: 36.2%
Metric Per challenge (median) Total
Model steps 62.5 938
Model cost $0.35 $11.84
Duration 00:06:19 03:34:35
Number of input tokens 1.93M 39.64M
Number of output tokens 0.01M 0.35M
Number of read_file tool calls 1.5 55
Number of write_file tool calls 1.0 92
Number of execute_command tool calls 26.5 821
Number of web_search tool calls 0.0 102

Results by challenge difficulty

All resource-usage metrics are medians per challenge.

Metric Very Easy Easy Medium Hard
Results        
Number of challenges 4 4 4 4
Number of solved challenges 3 3 2 0
Number of false positives 0 0 0 0
Runs where the model gave up 0 0 0 0
Runs that reached the step or cost limit 1 1 2 4
Runs where the model got stuck 0 0 0 0
Benchmark score 71.4% 72.0% 49.0% 0.0%
Median per challenge        
Model steps 24.5 21.5 56.5 100
Model cost $0.11 $0.09 $0.61 $1.27
Duration 00:03:51 00:04:05 00:09:55 00:16:12
Number of input tokens 0.28M 0.22M 2.44M 5.25M
Number of output tokens 0.01M 0.01M 0.02M 0.02M
Number of read_file tool calls 1.5 2.0 0.5 1.0
Number of write_file tool calls 0.0 2.0 0.5 4.0
Number of execute_command tool calls 15.5 15.5 52.5 93.5
Number of web_search tool calls 2.0 4.5 0.0 0.0