Solving Hack The Box Challenges with Grok 4.5
When I tested an older version of Grok this spring, my only comment was blunt: “grok-4.20 was useless.” So when Grok 4.5 was released a month ago and started receiving very positive reviews, I was quite surprised.
Now I’ve finally had a chance to test it against HTB challenges, and the team behind it deserves an apology. I’m not sure what the folks at xAI did, but the performance increase over the older version is jaw-dropping.
This blog post is part of a series of tests for the HTB-Challenger Benchmark. See the benchmark results page for all results and the benchmark methodology to learn how the benchmark is calculated.
During my testing, I watched this model crack one HTB challenge after another in a steady, confident way, and the final boss fight against the last challenge was exhilarating, even though it was ultimately unsuccessful. In the end, with a 90% score, it’s the undisputed new king of my leaderboard - not only because of its results, but also because of its speed (it had the fewest steps per challenge of all the models I’ve tested so far) and cost. Look at the Cost vs. Benchmark Score graph on the HTB-Challenger Benchmark page to see what I mean.
So let’s forget that useless old version. For me, Grok 4.5 is currently the best model I’ve tested on offensive-security challenges.
Overall benchmark results
- Number of challenges: 16
- Number of solved challenges: 15
- Number of false positives: 0
- Runs where the model gave up: 0
- Runs that reached the step or cost limit: 1
- Runs where the model got stuck: 0
- Benchmark score: 90.0%
| Metric | Per challenge (median) | Total |
|---|---|---|
| Model steps | 13.5 | 431 |
| Model cost | $0.25 | $12.83 |
| Duration | 00:05:48 | 03:10:27 |
| Number of input tokens | 0.28M | 19.04M |
| Number of output tokens | 0.01M | 0.45M |
Number of read_file tool calls |
0.0 | 16 |
Number of write_file tool calls |
0.0 | 6 |
Number of execute_command tool calls |
13.5 | 407 |
Number of web_search tool calls |
0.0 | 11 |
Results by challenge difficulty
Very Easy challenges
- Number of challenges: 4
- Number of solved challenges: 4
- Number of false positives: 0
- 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: 100.0%
| Metric | Per challenge (median) | Total |
|---|---|---|
| Model steps | 9.5 | 60 |
| Model cost | $0.09 | $0.83 |
| Duration | 00:01:34 | 00:11:32 |
| Number of input tokens | 0.08M | 1.30M |
| Number of output tokens | 0.00M | 0.03M |
Number of read_file tool calls |
0.5 | 6 |
Number of write_file tool calls |
0.0 | 1 |
Number of execute_command tool calls |
7.5 | 53 |
Number of web_search tool calls |
0.0 | 2 |
Easy challenges
- Number of challenges: 4
- Number of solved challenges: 4
- Number of false positives: 0
- 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: 100.0%
| Metric | Per challenge (median) | Total |
|---|---|---|
| Model steps | 13 | 48 |
| Model cost | $0.17 | $0.63 |
| Duration | 00:04:28 | 00:16:56 |
| Number of input tokens | 0.21M | 0.70M |
| Number of output tokens | 0.01M | 0.03M |
Number of read_file tool calls |
1.0 | 6 |
Number of write_file tool calls |
0.0 | 1 |
Number of execute_command tool calls |
11.0 | 45 |
Number of web_search tool calls |
1.5 | 7 |
Medium challenges
- Number of challenges: 4
- Number of solved challenges: 4
- Number of false positives: 0
- 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: 100.0%
| Metric | Per challenge (median) | Total |
|---|---|---|
| Model steps | 16 | 104 |
| Model cost | $0.34 | $3.29 |
| Duration | 00:06:41 | 00:35:59 |
| Number of input tokens | 0.43M | 4.89M |
| Number of output tokens | 0.01M | 0.09M |
Number of read_file tool calls |
0.0 | 1 |
Number of write_file tool calls |
0.0 | 1 |
Number of execute_command tool calls |
14.5 | 99 |
Number of web_search tool calls |
0.0 | 0 |
Hard challenges
- Number of challenges: 4
- Number of solved challenges: 3
- Number of false positives: 0
- Runs where the model gave up: 0
- Runs that reached the step or cost limit: 1
- Runs where the model got stuck: 0
- Benchmark score: 75.0%
| Metric | Per challenge (median) | Total |
|---|---|---|
| Model steps | 49 | 219 |
| Model cost | $1.54 | $8.08 |
| Duration | 00:24:02 | 02:05:59 |
| Number of input tokens | 2.69M | 12.14M |
| Number of output tokens | 0.04M | 0.30M |
Number of read_file tool calls |
0.0 | 3 |
Number of write_file tool calls |
0.5 | 3 |
Number of execute_command tool calls |
47.5 | 210 |
Number of web_search tool calls |
0.5 | 2 |