# Evaluating GPT-5.6 Sol on Hack The Box Challenges

> Source: <https://theaq.blog/2026/08/16/solving-htb-challenges-with-openai-gpt-5.6-sol.html>
> Published: 2026-08-16 16:10:31+00:00

# Evaluating GPT‑5.6 Sol on Hack The Box Challenges

For some personal observations about this model, please see the

[Solving Hack The Box Challenges with GPT-5.6]post.

This blog post is part of a series of tests for the

[HTB-Challenger Benchmark]The 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.

## 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.

## Overall benchmark results

**Number of challenges:** 16**Number of solved challenges:** 15**Number of false positives:** 1**Runs where the model gave up:** 0**Runs that reached the step or cost limit:** 0**Runs where the model got stuck:** 0**Benchmark score:** 87.2%

| Metric | Per challenge (median) | Total |
|---|---|---|
| Model steps | 8.5 | 274 |
| Model cost | $0.29 | $11.82 |
| Duration | 00:02:05 | 01:06:14 |
| Number of input tokens | 0.09M | 7.88M |
| Number of output tokens | 0.00M | 0.11M |
Number of `read_file` tool calls |
0.5 | 27 |
Number of `write_file` tool calls |
0.0 | 12 |
Number of `execute_command` tool calls |
8.5 | 271 |
Number of `web_search` tool calls |
0.0 | 7 |

## 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 | 4 | 4 | 4 | 3 |
| Number of false positives | 0 | 0 | 0 | 1 |
| Runs where the model gave up | 0 | 0 | 0 | 0 |
| Runs that reached the step or cost limit | 0 | 0 | 0 | 0 |
| Runs where the model got stuck | 0 | 0 | 0 | 0 |
| Benchmark score | 98.8% | 96.7% | 97.6% | 71.8% |
Median per challenge |
||||
| Model steps | 6 | 10 | 8.5 | 25 |
| Model cost | $0.10 | $0.18 | $0.32 | $1.49 |
| Duration | 00:00:49 | 00:01:35 | 00:02:07 | 00:06:35 |
| Number of input tokens | 0.03M | 0.05M | 0.11M | 1.08M |
| Number of output tokens | 0.00M | 0.00M | 0.00M | 0.01M |
Number of `read_file` tool calls |
0.5 | 1.0 | 0.5 | 0.0 |
Number of `write_file` tool calls |
0.0 | 0.5 | 0.5 | 0.5 |
Number of `execute_command` tool calls |
4.0 | 8.0 | 9.5 | 31.5 |
Number of `web_search` tool calls |
0.0 | 0.0 | 0.0 | 0.0 |